regina::Script Class Reference

A packet representing a Python script that can be run. More...

#include <packet/script.h>

Inheritance diagram for regina::Script:

Public Member Functions
	Script ()=default
	Initialises to a script with no text and no variables. More...
	Script (const Script &)=default
	Creates a new copy of the given script packet. More...
Script &	operator= (const Script &src)
	Sets this to be a copy of the given script packet. More...
void	swap (Script &other)
	Swaps the contents of this and the given script packet. More...
const std::string &	text () const
	Returns the complete text of this script. More...
void	setText (const std::string &newText)
	Replaces the complete text of this script with the given string. More...
void	append (const std::string &extraText)
	Adds the given text to the end of this script. More...
size_t	countVariables () const
	Returns the number of variables associated with this script. More...
const std::string &	variableName (size_t index) const
	Returns the name of the requested variable associated with this script. More...
long	variableIndex (const std::string &name) const
	Returns the index of the variable stored with the given name. More...
std::shared_ptr< Packet >	variableValue (size_t index) const
	Returns the value of the requested variable associated with this script. More...
std::shared_ptr< Packet >	variableValue (const std::string &name) const
	Returns the value of the variable stored with the given name. More...
void	setVariableName (size_t index, const std::string &name)
	Changes the name of an existing variable associated with this script. More...
void	setVariableValue (size_t index, std::weak_ptr< Packet > value={})
	Changes the value of an existing variable associated with this script. More...
bool	addVariable (const std::string &name, std::weak_ptr< Packet > value={})
	Attempts to add a new variable to be associated with this script. More...
const std::string &	addVariableName (const std::string &name, std::weak_ptr< Packet > value={})
	Adds a new variable to be associated with this script, changing its name if necessary. More...
void	removeVariable (const std::string &name)
	Removes the variable stored with the given name. More...
void	removeVariable (size_t index)
	Removes the variable stored at the given index. More...
void	removeAllVariables ()
	Removes all variables associated with this script. More...
void	listenVariables (PacketListener *listener)
	Registers the given packet listener to listen for events on all of packets identified by this script's variables. More...
void	unlistenVariables (PacketListener *listener)
	Deregisters the given packet listener from listening for events on all of packets identified by this script's variables. More...
bool	operator== (const Script &other) const
	Determines if this and the given script are identical. More...
bool	operator!= (const Script &other) const
	Determines if this and the given script are not identical. More...
void	writeTextShort (std::ostream &out) const override
	Writes a short text representation of this object to the given output stream. More...
void	writeTextLong (std::ostream &out) const override
	Writes a detailed text representation of this object to the given output stream. More...
std::string	str () const
	Returns a short text representation of this object. More...
std::string	utf8 () const
	Returns a short text representation of this object using unicode characters. More...
std::string	detail () const
	Returns a detailed text representation of this object. More...
Packet Identification
virtual PacketType	type () const =0
	Returns the unique integer ID representing this type of packet. More...
virtual std::string	typeName () const =0
	Returns an English name for this type of packet. More...
const std::string &	label () const
	Returns the label associated with this individual packet. More...
std::string	humanLabel () const
	Returns the label associated with this individual packet, adjusted if necessary for human-readable output. More...
std::string	adornedLabel (const std::string &adornment) const
	Returns the label of this packet adorned with the given string. More...
void	setLabel (const std::string &label)
	Sets the label associated with this individual packet. More...
std::string	fullName () const
	Returns a descriptive text string for the packet. More...
Tags
bool	hasTag (const std::string &tag) const
	Determines whether this packet has the given associated tag. More...
bool	hasTags () const
	Determines whether this packet has any associated tags at all. More...
bool	addTag (const std::string &tag)
	Associates the given tag with this packet. More...
bool	removeTag (const std::string &tag)
	Removes the association of the given tag with this packet. More...
void	removeAllTags ()
	Removes all associated tags from this packet. More...
const std::set< std::string > &	tags () const
	Returns the set of all tags associated with this packet. More...
Event Handling
bool	listen (PacketListener *listener)
	Registers the given packet listener to listen for events on this packet. More...
bool	isListening (PacketListener *listener)
	Determines whether the given packet listener is currently listening for events on this packet. More...
bool	unlisten (PacketListener *listener)
	Unregisters the given packet listener so that it no longer listens for events on this packet. More...
Tree Queries
bool	samePacket (const Packet &other) const
	Determines whether this and the given object refer to the same packet. More...
bool	hasParent () const
	Determines if this packet has a parent in the tree structure. More...
std::shared_ptr< Packet >	parent () const
	Determines the parent packet in the tree structure. More...
std::shared_ptr< Packet >	firstChild () const
	Determines the first child of this packet in the tree structure. More...
std::shared_ptr< Packet >	lastChild () const
	Determines the last child of this packet in the tree structure. More...
std::shared_ptr< Packet >	nextSibling () const
	Determines the next sibling of this packet in the tree structure. More...
std::shared_ptr< Packet >	prevSibling () const
	Determines the previous sibling of this packet in the tree structure. More...
std::shared_ptr< Packet >	root () const
	Determines the root of the tree to which this packet belongs. More...
unsigned	levelsDownTo (const Packet &descendant) const
	Counts the number of levels between this packet and its given descendant in the tree structure. More...
unsigned	levelsUpTo (const Packet &ancestor) const
	Counts the number of levels between this packet and its given ancestor in the tree structure. More...
bool	isAncestorOf (const Packet &descendant) const
	Determines if this packet is equal to or an ancestor of the given packet in the tree structure. More...
size_t	countChildren () const
	Returns the number of immediate children of this packet. More...
size_t	countDescendants () const
	Returns the total number of strict descendants of this packet. More...
size_t	totalTreeSize () const
	Determines the total number of packets in the tree or subtree for which this packet is matriarch. More...
Tree Manipulation
void	prepend (std::shared_ptr< Packet > child)
	Inserts the given packet as the first child of this packet. More...
void	insertChildFirst (std::shared_ptr< Packet > child)
	Deprecated routine that inserts the given packet as the first child of this packet. More...
void	append (std::shared_ptr< Packet > child)
	Inserts the given packet as the last child of this packet. More...
void	insertChildLast (std::shared_ptr< Packet > child)
	Deprecated routine that inserts the given packet as the last child of this packet. More...
void	insert (std::shared_ptr< Packet > newChild, std::shared_ptr< Packet > prevChild)
	Inserts the given packet as a child of this packet at the given location in this packet's child list. More...
void	insertChildAfter (std::shared_ptr< Packet > newChild, std::shared_ptr< Packet > prevChild)
	Deprecated routine that inserts the given packet as a child of this packet at the given location in this packet's child list. More...
void	makeOrphan ()
	Cuts this packet away from its parent in the tree structure and instead makes it the root of its own tree. More...
void	reparent (const std::shared_ptr< Packet > &newParent, bool first=false)
	Cuts this packet away from its parent in the tree structure, and inserts it as a child of the given packet instead. More...
void	transferChildren (const std::shared_ptr< Packet > &newParent)
	Cuts all of this packet's children out of the packet tree, and reinserts them as children of the given packet instead. More...
void	swapWithNextSibling ()
	Swaps this packet with its next sibling in the sequence of children beneath their common parent packet. More...
void	moveUp (unsigned steps=1)
	Moves this packet the given number of steps towards the beginning of its sibling list. More...
void	moveDown (unsigned steps=1)
	Moves this packet the given number of steps towards the end of its sibling list. More...
void	moveToFirst ()
	Moves this packet to be the first in its sibling list. More...
void	moveToLast ()
	Moves this packet to be the last in its sibling list. More...
void	sortChildren ()
	Sorts the immediate children of this packet according to their packet labels. More...
Searching and Iterating
SubtreeIterator< false >	begin ()
	Returns a C++ non-const iterator at the beginning of the range of packets in the subtree rooted at this packet. More...
SubtreeIterator< true >	begin () const
	Returns a C++ const iterator at the beginning of the range of packets in the subtree rooted at this packet. More...
SubtreeIterator< false >	end ()
	Returns a C++ non-const iterator beyond the end of the range of packets in the subtree rooted at this packet. More...
SubtreeIterator< true >	end () const
	Returns a C++ const iterator beyond the end of the range of packets in the subtree rooted at this packet. More...
auto	__iter__ () const
	Returns a Python iterator over the packets in the subtree rooted at this packet. More...
PacketDescendants< false >	descendants ()
	Returns a lightweight object for iterating through all strict descendants of this packet in the packet tree. More...
PacketDescendants< true >	descendants () const
	Returns a lightweight object for iterating through all strict descendants of this packet in the packet tree. More...
PacketChildren< false >	children ()
	Returns a lightweight object for iterating through the immediate children of this packet. More...
PacketChildren< true >	children () const
	Returns a lightweight object for iterating through the immediate children of this packet. More...
std::shared_ptr< Packet >	nextTreePacket ()
	Finds the next packet after this in a complete depth-first iteration of the entire tree structure to which this packet belongs. More...
std::shared_ptr< const Packet >	nextTreePacket () const
	Finds the next packet after this in a complete depth-first iteration of the entire tree structure to which this packet belongs. More...
std::shared_ptr< Packet >	nextTreePacket (PacketType type)
	Finds the next packet after this of the requested type in a complete depth-first iteration of the entire tree structure. More...
std::shared_ptr< const Packet >	nextTreePacket (PacketType type) const
	Finds the next packet after this of the requested type in a complete depth-first iteration of the entire tree structure. More...
std::shared_ptr< Packet >	firstTreePacket (PacketType type)
	Finds the first packet of the requested type in a complete depth-first iteration of the tree structure. More...
std::shared_ptr< const Packet >	firstTreePacket (PacketType type) const
	Finds the first packet of the requested type in a complete depth-first iteration of the tree structure. More...
std::shared_ptr< Packet >	findPacketLabel (const std::string &label)
	Finds the packet with the requested label in the tree or subtree for which this packet is matriarch. More...
std::shared_ptr< const Packet >	findPacketLabel (const std::string &label) const
	Finds the packet with the requested label in the tree or subtree for which this packet is matriarch. More...
Cloning
std::shared_ptr< Packet >	cloneAsSibling (bool cloneDescendants=false, bool end=true) const
	Clones this packet (and possibly its descendants), assigns to it a suitable unused label and inserts the clone into the tree as a sibling of this packet. More...

Protected Member Functions
std::shared_ptr< Packet >	internalClonePacket () const override
	Makes a new copy of this packet. More...
void	writeXMLPacketData (std::ostream &out, FileFormat format, bool anon, PacketRefs &refs) const override
	Writes a chunk of XML containing the full subtree with this packet as matriarch. More...
void	addPacketRefs (PacketRefs &refs) const override
	Records which other packets this packet refers to within the overall packet tree. More...

File I/O
bool	save (const char *filename, bool compressed=true, FileFormat format=REGINA_CURRENT_FILE_FORMAT) const
	Saves the subtree rooted at this packet to the given Regina data file, using Regina's native XML file format. More...
bool	save (std::ostream &s, bool compressed=true, FileFormat format=REGINA_CURRENT_FILE_FORMAT) const
	Writes the subtree rooted at this packet to the given output stream, in the format of a Regina XML data file. More...
void	writeXMLFile (std::ostream &out, FileFormat format=REGINA_CURRENT_FILE_FORMAT) const
	Writes the subtree rooted at this packet to the given output stream in Regina's native XML file format. More...
std::string	internalID () const
	Returns a unique string ID that identifies this packet. More...
template<typename... Args>
void	writeXMLHeader (std::ostream &out, const char *element, FileFormat format, bool anon, PacketRefs &refs, bool newline, std::pair< const char *, Args >... attr) const
	Writes the opening XML tag for this packet. More...
void	writeXMLTreeData (std::ostream &out, FileFormat format, PacketRefs &refs) const
	Writes any generic XML sub-elements for this packet that come from the packet tree. More...
void	writeXMLFooter (std::ostream &out, const char *element, FileFormat format) const
	Writes the closing XML tag for this packet. More...
void	writeXMLAnon (std::ostream &out, FileFormat format, PacketRefs &refs, const Packet &p) const
	Writes the given packet inside its own anonymous block. More...
using	PacketRefs = std::map< const Packet *, bool >
	Used during the XML output routines to manage references between packets in an XML data file. More...

Detailed Description

A packet representing a Python script that can be run.

A script consists of two parts: (i) the text, which contains the Python code; and (ii) a set of variables, which refer to packets in your packet tree. When running a script, the variables should be instantiated in the default namespace before the script is run.

The way variables are stored has changed as of Regina 7.0:

• the value of each variable is now stored as a std::weak_ptr<Packet>;
• scripts do not listen to packet events on their variables.

This means that:

• If a packet is stored as the value of some script variable, this does not prevent the packet from being destroyed (since the script only holds weak pointers).
• If such a packet changes its packet label or is destroyed, the script will not notify its own listeners of the change. If a user interface needs to know about this change (e.g., because it shows packet labels of script variables in a visual table), it will need to set up packet listeners for the individual variables - it is no longer enough just to listen on the script itself. Note that packet labels are completely independent of the variable names stored in the script.
• If such a packet is destroyed, the script will behave correctly: any subsequent request to retrieve the value of the script variable will return a null pointer (not an invalid pointer to a non-existent packet).

For historical reference, the previous behaviour was:

• In Regina 6.0.1 and earlier (before Regina switched to widespread use of std::shared_ptr for packets), scripts would notify their own listeners when a variable packet was destroyed or changed its packet label. This was implemented by having each script listen for packet events on its own variables.
• In Regina 4.94 and earlier (before the file format supported cross-referencing between packets), script variables were stored purely by their packet labels (not pointers to the packets themselves).

Like all packet types, this class does not support C++ move semantics since this would interfere with the structure of the packet tree. It does support copy construction, copy assignment and swaps; however, these operations only copy/swap the mathematical content, not the packet infrastructure (e.g., they do not touch packet labels, or the packet tree, or event listeners).

Member Typedef Documentation

PacketRefs

using regina::Packet::PacketRefs = std::map<const Packet*, bool>

protectedinherited

Used during the XML output routines to manage references between packets in an XML data file.

If some packet needs to refer to a packet P, then P will appear as a key this map; the corresponding value will be false initially, and will change to true once P has been written to the XML file.

Constructor & Destructor Documentation

Script() [1/2]

regina::Script::Script ( )

default

Initialises to a script with no text and no variables.

Script() [2/2]

regina::Script::Script ( const Script &  )

default

Creates a new copy of the given script packet.

Like all packet types, this only copies the script content, not the packet infrastructure (e.g., it will not copy the packet label, it will not clone the given packet's children, and it will not insert the new packet into any packet tree).

Member Function Documentation

__iter__()

auto regina::Packet::__iter__ ( ) const

inherited

Returns a Python iterator over the packets in the subtree rooted at this packet.

Subtree iteration is depth-first, where a parent packet is always processed before its descendants. In particular, this packet (as the root of the subtree) will be processed first.

In Python, each packet can be treated as an iterable object, with the effect of iterating through the corresponding subtree:

subtree = ...
for p in subtree:
    ...

Regina also supplies Python users with a member function Packet.subtree(), which returns an iterable object. Iterating over Packet.subtree() is exactly the same as iterating the packet itself; the subtree() function is offered because the intention may be clearer for readers.

See also descendants() for iterating through just the strict descendants in the subtree (i.e., excluding this packet itself), and children() for iterating just through the immediate children of this packet (not the full subtree).

C++

Not present. For C++ users, Packet provides the usual begin() and end() functions instead. In particular, you can iterate over a packet subtree in the usual C++ way using a range-based for loop.

Returns

an iterator over the subtree rooted at this packet.

addPacketRefs()

void regina::Script::addPacketRefs ( PacketRefs &  refs ) const

inlineoverrideprotectedvirtual

Records which other packets this packet refers to within the overall packet tree.

For each packet p that this packet refers to, this routine should insert the pair (p, false) into the given map.

This will be run before writing the packet tree to an XML data file. By recording that this packet refers to some other packet p, this will ensure that the XML header for p will include an explicit ID that this packet can then refer to.

Later on, as the XML is written, the value refs[p] will be changed from false to true once p has been written.

If your packet requires that the contents of p appear before this packet it the XML data file, then writeXMLPacketData() should check refs to see if p has already been written, and if not, it should write p in a new anonymous block.

It is fine if p does not actually belong to this packet tree. However, in this case writeXMLPacketData() must take responsibility to ensure that p is written to file. This would need to be done via writeXMLAnon(); moreover, as before, it should only be done only after checking refs to ensure this p has not already been written.

The default implementation of this routine does nothing.

Parameters

refs	the map in which any dependencies should be recorded.

Reimplemented from regina::Packet.

addTag()

bool regina::Packet::addTag ( const std::string &  tag )

inherited

Associates the given tag with this packet.

Each packet can have an arbitrary set of string tags associated with it. The tags are not used by this calculation engine; the feature is provided for whatever use a developer or user chooses to make of it.

Tags are case-sensitive. Tags associated with a single packet must be distinct, i.e., a particular tag cannot be associated more than once with the same packet.

Precondition

The given tag is not the empty string.

Parameters

tag	the tag to add.

Returns

true if the given tag was successfully added, or false if the given tag was already present beforehand.

addVariable()

bool regina::Script::addVariable ( const std::string &  name, std::weak_ptr< Packet >  value = {}  )

inline

Attempts to add a new variable to be associated with this script.

If a variable with the given name is already stored, this routine will do nothing.

If you need to ensure that a new variable is always added, even if the variable name needs to change, see the routine addVariableName() instead.

Warning

The index of the new variable might not be countVariables()-1, and this operation may change the indices of other variables also. This is because (at present) variables are kept stored in sorted order by name.

Parameters

name	the name of the new variable.
value	the value of the new variable. This is allowed to be a null pointer, and if the argument is omitted then a null pointer will be used.

Returns

true if the variable was successfully added, or false if a variable with the given name was already stored.

addVariableName()

const std::string & regina::Script::addVariableName	(	const std::string &	name,
		std::weak_ptr< Packet >	value = {}
	)

Adds a new variable to be associated with this script, changing its name if necessary.

If the given variable name does not already exist as a variable name in this script, then it will be used without modification. Otherwise a new variable name will be constructed by appending additional characters to name.

Warning

The index of the new variable might not be countVariables()-1, and this operation may change the indices of other variables also. This is because (at present) variables are kept stored in sorted order by name.

Parameters

name	the string upon which the new variable name will be based.
value	the value of the new variable. This is allowed to be a null pointer, and if the argument is omitted then a null pointer will be used.

Returns

the name of the variable that was added; this might or might not be equal to name.

adornedLabel()

std::string regina::Packet::adornedLabel ( const std::string &  adornment ) const

inherited

Returns the label of this packet adorned with the given string.

An adornment typically shows how a packet has been created and/or modified. For instance, the adornment argument might be "Filled", or "Summand #1".

The way in which the packet label is adorned depends upon the label itself (in particular, an empty packet label will be handled in a sensible way). The way in which the packet label is adorned is subject to change in future versions of Regina.

Note that, whilst this routine returns a modified version of the packet label, the label itself will not be permamently changed.

Parameters

adornment

the string that will be used to adorn this packet label. The adornment should just be a piece of English, ideally beginning with an upper-case letter. It should not contain any surrounding punctuation such as brackets or a dash (this will be added automatically by this routine as required).

Returns

a copy of the packet label with the given adornment.

append() [1/2]

void regina::Script::append ( const std::string &  extraText )

inline

Adds the given text to the end of this script.

Parameters

extraText

the text to add.

append() [2/2]

void regina::Packet::append ( std::shared_ptr< Packet >  child )

inherited

Inserts the given packet as the last child of this packet.

This packet will take ownership of child, in the sense that every parent packet stores (either directly or indirectly) a shared_ptr to every one of its descendants in the packet tree.

In Regina 7.0 and earlier, this routine was called insertChildLast().

This routine takes small constant time.

Precondition

The given child has no parent packet.

This packet is not a descendant of the given child.

Exceptions

InvalidArgument

The argument child already has a parent packet. Note that, although this tests one of our preconditions, there are other preconditions that are not tested, and for which no exceptions are thrown.

Parameters

child

the child to insert.

begin() [1/2]

SubtreeIterator< false > regina::Packet::begin ( )

inlineinherited

Returns a C++ non-const iterator at the beginning of the range of packets in the subtree rooted at this packet.

Subtree iteration is depth-first, where a parent packet is always processed before its descendants. In particular, the iterator returned by begin() will always point to this packet itself.

In C++, these begin() and end() routines allow you to iterate through an entire packet subtree using range-based for loops:

std::shared_ptr<Packet> subtree = ...;
for (Packet& p : *subtree) { ... }

Since Regina 7.0, the return type is templated in order to support both const and non-const iteration. It is recommended that you just use auto if you need to store a local copy of the returned iterator.

See also descendants() for iterating through just the strict descendants in the subtree (i.e., excluding this packet itself), and children() for iterating just through the immediate children of this packet (not the full subtree).

Python

Not present. For Python users, Packet implements the Python iterable interface. You can iterate over the packets in a subtree in the usual Python way, by treating the subtree root as you would any native Python container. See iter() for details.

Returns

an iterator at the beginning of this subtree.

begin() [2/2]

SubtreeIterator< true > regina::Packet::begin ( ) const

inlineinherited

Returns a C++ const iterator at the beginning of the range of packets in the subtree rooted at this packet.

Subtree iteration is depth-first, where a parent packet is always processed before its descendants. In particular, the iterator returned by begin() will always point to this packet itself.

In C++, these begin() and end() routines allow you to iterate through an entire packet subtree using range-based for loops:

std::shared_ptr<const Packet> subtree = ...;
for (const Packet& p : *subtree) { ... }

Since Regina 7.0, the return type is templated in order to support both const and non-const iteration. It is recommended that you just use auto if you need to store a local copy of the returned iterator.

See also descendants() for iterating through just the strict descendants in the subtree (i.e., excluding this packet itself), and children() for iterating just through the immediate children of this packet (not the full subtree).

Python

Not present. For Python users, Packet implements the Python iterable interface. You can iterate over the packets in a subtree in the usual Python way, by treating the subtree root as you would any native Python container. See iter() for details.

Returns

an iterator at the beginning of this subtree.

children() [1/2]

PacketChildren< false > regina::Packet::children ( )

inlineinherited

Returns a lightweight object for iterating through the immediate children of this packet.

This routine allows you to iterate through the immediate children of a given packet using range-based for loops:

std::shared_ptr<Packet> parent = ...;
for (Packet& child : parent->children()) { ... }

In Python, this routine returns an iterable object:

parent = ...
for child in parent.children():
    ...

This function returns a lightweight object in the sense that it does not generate a full list of children in advance, but instead just returns a small iterator that visits each child as required. In particular, this routine has small constant time and memory.

Since Regina 7.0, the return type is templated in order to support both const and non-const iteration. It is recommended that you just use auto if you need to store a local copy of the returned object.

See begin() and end(), as well as descendants(), for iterating through the subtree rooted at this packet (not just the immediate children).

Returns

an object for iterating through the children of this packet.

children() [2/2]

PacketChildren< true > regina::Packet::children ( ) const

inlineinherited

Returns a lightweight object for iterating through the immediate children of this packet.

This routine allows you to iterate through the immediate children of a given packet using range-based for loops:

std::shared_ptr<const Packet> parent = ...;
for (const Packet& child : parent->children()) { ... }

This function returns a lightweight object in the sense that it does not generate a full list of children in advance, but instead just returns a small iterator that visits each child as required. In particular, this routine has small constant time and memory.

Since Regina 7.0, the return type is templated in order to support both const and non-const iteration. It is recommended that you just use auto if you need to store a local copy of the returned object.

See begin() and end(), as well as descendants(), for iterating through the subtree rooted at this packet (not just the immediate children).

Returns

an object for iterating through the children of this packet.

cloneAsSibling()

std::shared_ptr< Packet > regina::Packet::cloneAsSibling ( bool  cloneDescendants = false, bool  end = true  ) const

inherited

Clones this packet (and possibly its descendants), assigns to it a suitable unused label and inserts the clone into the tree as a sibling of this packet.

Note that any string tags associated with this packet will not be cloned.

If this packet has no parent in the tree structure, no clone will be created and null will be returned.

In Regina 6.0.1 and earlier, this function was called clone(). It was renamed in Regina 7.0 to emphasise that this is not just a deep copy, and is not guaranteed to succeed.

Note

Since Regina 7.0, if a normal surface/hypersurface or angle structure list is cloned, then the new clone will refer back to the original triangulation, even if we are cloning an entire packet tree. This is because there is no guarantee that the original triangulation was cloned also (it could live outside the cloned subtree, or might not be part of a packet tree at all).

Parameters

cloneDescendants	true if the descendants of this packet should also be cloned and inserted as descendants of the new packet. If this is passed as false (the default), only this packet will be cloned.
end	true if the new packet should be inserted at the end of the parent's list of children (the default), or false if the new packet should be inserted as the sibling immediately after this packet.

Returns

the newly inserted packet, or null if this packet has no parent.

countChildren()

size_t regina::Packet::countChildren ( ) const

inherited

Returns the number of immediate children of this packet.

Grandchildren and so on are not counted.

Returns

the number of immediate children.

countDescendants()

size_t regina::Packet::countDescendants ( ) const

inlineinherited

Returns the total number of strict descendants of this packet.

This includes children, grandchildren and so on. This packet is not included in the count.

Returns

the total number of strict descendants.

countVariables()

size_t regina::Script::countVariables ( ) const

inline

Returns the number of variables associated with this script.

Returns

the number of variables.

descendants() [1/2]

PacketDescendants< false > regina::Packet::descendants ( )

inlineinherited

Returns a lightweight object for iterating through all strict descendants of this packet in the packet tree.

The order of iteration is exactly the same as when iterating over the full subtree rooted at this packet (as offered by Packet::begin() and Packet::end()), except that the iteration excludes this packet itself. In particular, the iteration is depth-first, and each packet in the subtree is processed before its own descendants.

This routine allows you to iterate through all strict descendants of a given packet using range-based for loops:

std::shared_ptr<Packet> parent = ...;
for (Packet& desc : parent->descendants()) { ... }

In Python, this routine returns an iterable object:

parent = ...
for desc in parent.descendants():
    ...

This function returns a lightweight object in the sense that it does not generate a full list of descendants in advance, but instead just returns a small iterator that visits each descendant as required. In particular, this routine has small constant time and memory.

Since Regina 7.0, the return type is templated in order to support both const and non-const iteration. It is recommended that you just use auto if you need to store a local copy of the returned object.

See also begin() and end() for iterating through the entire subtree including this packet, and children() for iterating over just this packet's immediate children.

Returns

an object for iterating through the strict descendants of this packet.

descendants() [2/2]

PacketDescendants< true > regina::Packet::descendants ( ) const

inlineinherited

Returns a lightweight object for iterating through all strict descendants of this packet in the packet tree.

The order of iteration is exactly the same as when iterating over the full subtree rooted at this packet (as offered by Packet::begin() and Packet::end()), except that the iteration excludes this packet itself. In particular, the iteration is depth-first, and each packet in the subtree is processed before its own descendants.

This routine allows you to iterate through all strict descendants of a given packet using range-based for loops:

std::shared_ptr<const Packet> parent = ...;
for (const Packet& desc : parent->descendants()) { ... }

This function returns a lightweight object in the sense that it does not generate a full list of descendants in advance, but instead just returns a small iterator that visits each descendant as required. In particular, this routine has small constant time and memory.

Since Regina 7.0, the return type is templated in order to support both const and non-const iteration. It is recommended that you just use auto if you need to store a local copy of the returned object.

See also begin() and end() for iterating through the entire subtree including this packet, and children() for iterating over just this packet's immediate children.

Returns

an object for iterating through the strict descendants of this packet.

detail()

std::string regina::Output< Packet , false >::detail ( ) const

inherited

Returns a detailed text representation of this object.

This text may span many lines, and should provide the user with all the information they could want. It should be human-readable, should not contain extremely long lines (which cause problems for users reading the output in a terminal), and should end with a final newline. There are no restrictions on the underlying character set.

Returns

a detailed text representation of this object.

end() [1/2]

SubtreeIterator< false > regina::Packet::end ( )

inlineinherited

Returns a C++ non-const iterator beyond the end of the range of packets in the subtree rooted at this packet.

In C++, these begin() and end() routines allow you to iterate through an entire packet subtree using range-based for loops.

See the begin() documentation for further details.

Python

Not present. For Python users, Packet implements the Python iterable interface. You can iterate over the packets in a subtree in the usual Python way, by treating the subtree root as you would any native Python container. See iter() for details.

Returns

an iterator beyond the end of this subtree.

end() [2/2]

SubtreeIterator< true > regina::Packet::end ( ) const

inlineinherited

Returns a C++ const iterator beyond the end of the range of packets in the subtree rooted at this packet.

In C++, these begin() and end() routines allow you to iterate through an entire packet subtree using range-based for loops.

See the begin() documentation for further details.

Python

Not present. For Python users, Packet implements the Python iterable interface. You can iterate over the packets in a subtree in the usual Python way, by treating the subtree root as you would any native Python container. See iter() for details.

Returns

an iterator beyond the end of this subtree.

findPacketLabel() [1/2]

std::shared_ptr< Packet > regina::Packet::findPacketLabel ( const std::string &  label )

inherited

Finds the packet with the requested label in the tree or subtree for which this packet is matriarch.

Note that label comparisons are case sensitive.

Parameters

label

the label to search for.

Returns

the packet with the requested label, or null if there is no such packet.

findPacketLabel() [2/2]

std::shared_ptr< const Packet > regina::Packet::findPacketLabel ( const std::string &  label ) const

inherited

Finds the packet with the requested label in the tree or subtree for which this packet is matriarch.

Note that label comparisons are case sensitive.

Parameters

label

the label to search for.

Returns

the packet with the requested label, or null if there is no such packet.

firstChild()

std::shared_ptr< Packet > regina::Packet::firstChild ( ) const

inlineinherited

Determines the first child of this packet in the tree structure.

This routine takes small constant time.

Returns

the first child packet, or null if there is none.

firstTreePacket() [1/2]

std::shared_ptr< Packet > regina::Packet::firstTreePacket ( PacketType  type )

inlineinherited

Finds the first packet of the requested type in a complete depth-first iteration of the tree structure.

Note that this packet must be the matriarch of the entire tree.

A parent packet is always reached before its children. The tree matriarch will be the first packet visited in a complete depth-first iteration.

Parameters

type	the type of packet to search for.

Returns

the first such packet, or null if there are no packets of the requested type.

firstTreePacket() [2/2]

std::shared_ptr< const Packet > regina::Packet::firstTreePacket ( PacketType  type ) const

inlineinherited

Finds the first packet of the requested type in a complete depth-first iteration of the tree structure.

Note that this packet must be the matriarch of the entire tree.

A parent packet is always reached before its children. The tree matriarch will be the first packet visited in a complete depth-first iteration.

Parameters

type	the type of packet to search for.

Returns

the first such packet, or null if there are no packets of the requested type.

fullName()

std::string regina::Packet::fullName ( ) const

inherited

Returns a descriptive text string for the packet.

The string is of the form label (packet-type).

The packet label will be adjusted for human-readable output according to the behaviour of humanLabel().

Returns

the descriptive text string.

hasParent()

bool regina::Packet::hasParent ( ) const

inlineinherited

Determines if this packet has a parent in the tree structure.

This is equivalent to, but slightly faster than, testing whether parent() returns a null pointer.

Returns

if and only if this packet has a parent.

hasTag()

bool regina::Packet::hasTag ( const std::string &  tag ) const

inlineinherited

Determines whether this packet has the given associated tag.

Each packet can have an arbitrary set of string tags associated with it. The tags are not used by this calculation engine; the feature is provided for whatever use a developer or user chooses to make of it.

Tags are case-sensitive. Tags associated with a single packet must be distinct, i.e., a particular tag cannot be associated more than once with the same packet.

Parameters

tag	the tag to search for.

Returns

true if the given tag is found, false otherwise.

hasTags()

bool regina::Packet::hasTags ( ) const

inlineinherited

Determines whether this packet has any associated tags at all.

Each packet can have an arbitrary set of string tags associated with it. The tags are not used by this calculation engine; the feature is provided for whatever use a developer or user chooses to make of it.

Tags are case-sensitive. Tags associated with a single packet must be distinct, i.e., a particular tag cannot be associated more than once with the same packet.

Returns

true if this packet has any tags, false otherwise.

humanLabel()

std::string regina::Packet::humanLabel ( ) const

inlineinherited

Returns the label associated with this individual packet, adjusted if necessary for human-readable output.

In particular, if the packet has no label assigned then this routine will return "(no label)", not the empty string.

Warning

The method by which this routine adjusts packet labels is subject to change in future versions of Regina.

Returns

this individual packet's label.

insert()

void regina::Packet::insert ( std::shared_ptr< Packet >  newChild, std::shared_ptr< Packet >  prevChild  )

inherited

Inserts the given packet as a child of this packet at the given location in this packet's child list.

This packet will take ownership of child, in the sense that every parent packet stores (either directly or indirectly) a shared_ptr to every one of its descendants in the packet tree.

In Regina 7.0 and earlier, this routine was called insertChildAfter().

This routine takes small constant time.

Precondition

Parameter newChild has no parent packet.

This packet is already the parent of prevChild.

This packet is not a descendant of newChild.

Exceptions

InvalidArgument

The argument newChild already has a parent packet, and/or the argument prevChild is non-null and does not have this packet as its parent. Note that, although this tests some of our preconditions, there are other preconditions that are not tested, and for which no exceptions are thrown.

Parameters

newChild	the child to insert.
prevChild	the preexisting child of this packet after which newChild will be inserted, or null if newChild is to be the first child of this packet.

insertChildAfter()

void regina::Packet::insertChildAfter ( std::shared_ptr< Packet >  newChild, std::shared_ptr< Packet >  prevChild  )

inlineinherited

Deprecated routine that inserts the given packet as a child of this packet at the given location in this packet's child list.

Deprecated:

This routine has been renamed to insert(). See insert() for further details.

Precondition

Parameter newChild has no parent packet.

This packet is already the parent of prevChild.

This packet is not a descendant of newChild.

Exceptions

InvalidArgument

The argument newChild already has a parent packet, and/or the argument prevChild is non-null and does not have this packet as its parent. Note that, although this tests some of our preconditions, there are other preconditions that are not tested, and for which no exceptions are thrown.

Parameters

newChild	the child to insert.
prevChild	the preexisting child of this packet after which newChild will be inserted, or null if newChild is to be the first child of this packet.

insertChildFirst()

void regina::Packet::insertChildFirst ( std::shared_ptr< Packet >  child )

inlineinherited

Deprecated routine that inserts the given packet as the first child of this packet.

Deprecated:

This routine has been renamed to prepend(). See prepend() for further details.

Precondition

The given child has no parent packet.

This packet is not a descendant of the given child.

Exceptions

InvalidArgument

The argument child already has a parent packet. Note that, although this tests one of our preconditions, there are other preconditions that are not tested, and for which no exceptions are thrown.

Parameters

child

the child to insert.

insertChildLast()

void regina::Packet::insertChildLast ( std::shared_ptr< Packet >  child )

inlineinherited

Deprecated routine that inserts the given packet as the last child of this packet.

Deprecated:

This routine has been renamed to append(). See append() for further details.

Precondition

The given child has no parent packet.

This packet is not a descendant of the given child.

Exceptions

InvalidArgument

The argument child already has a parent packet. Note that, although this tests one of our preconditions, there are other preconditions that are not tested, and for which no exceptions are thrown.

Parameters

child

the child to insert.

internalClonePacket()

std::shared_ptr< Packet > regina::Script::internalClonePacket ( ) const

overrideprotectedvirtual

Makes a new copy of this packet.

This routine should not insert the new packet into the tree structure, clone the packet's associated tags or give the packet a label. It should also not clone any descendants of this packet.

You may assume that the new packet will eventually be inserted into the tree beneath either the same parent as this packet or a clone of that parent.

Returns

the newly created packet.

Implements regina::Packet.

internalID()

std::string regina::Packet::internalID ( ) const

inherited

Returns a unique string ID that identifies this packet.

The user has no control over this ID, and it is not human readable. It is guaranteed to remain fixed throughout the lifetime of the program for a given packet, and it is guaranteed not to clash with the ID of any other packet.

If you change the contents of a packet, its ID will not change.

If you clone a packet, the new clone will receive a different ID. If you save and then load a packet to/from file, the ID will change. These behaviours are necessary to ensure that IDs remain unique (since, for instance, you could load several copies of the same data file into memory simultaneously).

The ID is implemented as an encoding of the underlying C++ pointer. This encoding is subject to change in later versions of Regina.

Returns

a unique ID that identifies this packet.

isAncestorOf()

bool regina::Packet::isAncestorOf ( const Packet &  descendant ) const

inherited

Determines if this packet is equal to or an ancestor of the given packet in the tree structure.

Parameters

descendant

the other packet whose relationships we are examining.

Returns

true if and only if this packet is equal to or an ancestor of descendant.

isListening()

bool regina::Packet::isListening ( PacketListener *  listener )

inlineinherited

Determines whether the given packet listener is currently listening for events on this packet.

See the PacketListener class notes for details.

Parameters

listener

the listener to search for.

Returns

true if the given listener is currently registered with this packet, or false otherwise.

label()

const std::string & regina::Packet::label ( ) const

inlineinherited

Returns the label associated with this individual packet.

An example is MyTriangulation.

Returns

this individual packet's label.

lastChild()

std::shared_ptr< Packet > regina::Packet::lastChild ( ) const

inlineinherited

Determines the last child of this packet in the tree structure.

This routine takes small constant time.

Returns

the last child packet, or null if there is none.

levelsDownTo()

unsigned regina::Packet::levelsDownTo ( const Packet &  descendant ) const

inherited

Counts the number of levels between this packet and its given descendant in the tree structure.

If descendant is this packet, the number of levels is zero.

Precondition

This packet is equal to descendant, or can be obtained from descendant using only child-to-parent steps.

Exceptions

FailedPrecondition

The argument descendant is not equal to or a descendant of this packet.

Parameters

descendant

the packet whose relationship with this packet we are examining.

Returns

the number of levels difference.

levelsUpTo()

unsigned regina::Packet::levelsUpTo ( const Packet &  ancestor ) const

inlineinherited

Counts the number of levels between this packet and its given ancestor in the tree structure.

If ancestor is this packet, the number of levels is zero.

Precondition

This packet is equal to ancestor, or can be obtained from ancestor using only parent-to-child steps.

Exceptions

FailedPrecondition

This packet is not equal to or a descendant of the argument descendant.

Parameters

ancestor

the packet whose relationship with this packet we are examining.

Returns

the number of levels difference.

listen()

bool regina::Packet::listen ( PacketListener *  listener )

inherited

Registers the given packet listener to listen for events on this packet.

See the PacketListener class notes for details.

Parameters

listener

the listener to register.

Returns

true if the given listener was successfully registered, or false if the given listener was already registered beforehand.

listenVariables()

void regina::Script::listenVariables ( PacketListener *  listener )

inline

Registers the given packet listener to listen for events on all of packets identified by this script's variables.

This is a one-off operation: if the script variables should change later on, the given listener will not be registered and/or deregistered to reflect the new variable values.

This routine is safe to call if some variables have null values, and/or if the same packet is identified by multiple variables.

Parameters

listener

the listener to register with all packets identified by the script variables.

makeOrphan()

void regina::Packet::makeOrphan ( )

inherited

Cuts this packet away from its parent in the tree structure and instead makes it the root of its own tree.

The tree information for both this packet and its parent will be updated.

The old parent will relinquish ownership of this packet. This means that, even if the old parent remains alive, once the last shared_ptr to this packet is destroyed then this packet itself will be destroyed also.

This makeOrphan() function is the preferred way to "delete" a packet p from a larger packet tree: simply orphan p and then dispose of any outstanding shared pointers to it (if you have any).

Even if you are not holding a shared_ptr to this packet yourself, this routine is still safe to use: it will keep an internal shared_ptr as a "guard" until makeOrphan() has completed its work, at which point the packet will be safely destroyed.

This routine takes small constant time. It is safe to use regardless of whether this packet currently has a parent or not.

moveDown()

void regina::Packet::moveDown ( unsigned  steps = 1 )

inherited

Moves this packet the given number of steps towards the end of its sibling list.

If the number of steps is larger than the greatest possible movement, the packet will be moved to the very end of its sibling list.

This routine takes time proportional to the number of steps.

Precondition

The given number of steps is strictly positive.

Parameters

steps

the number of steps down to move.

moveToFirst()

void regina::Packet::moveToFirst ( )

inherited

Moves this packet to be the first in its sibling list.

This routine takes small constant time.

moveToLast()

void regina::Packet::moveToLast ( )

inherited

Moves this packet to be the last in its sibling list.

This routine takes small constant time.

moveUp()

void regina::Packet::moveUp ( unsigned  steps = 1 )

inherited

Moves this packet the given number of steps towards the beginning of its sibling list.

If the number of steps is larger than the greatest possible movement, the packet will be moved to the very beginning of its sibling list.

This routine takes time proportional to the number of steps.

Precondition

The given number of steps is strictly positive.

Parameters

steps

the number of steps up to move.

nextSibling()

std::shared_ptr< Packet > regina::Packet::nextSibling ( ) const

inlineinherited

Determines the next sibling of this packet in the tree structure.

This is the child of the parent that follows this packet.

This routine takes small constant time.

Returns

the next sibling of this packet, or null if there is none.

nextTreePacket() [1/4]

std::shared_ptr< Packet > regina::Packet::nextTreePacket ( )

inherited

Finds the next packet after this in a complete depth-first iteration of the entire tree structure to which this packet belongs.

Note that this packet need not be the tree matriarch.

A parent packet is always reached before its children. The tree matriarch will be the first packet visited in a complete depth-first iteration.

Returns

the next packet, or null if this is the last packet in such an iteration.

nextTreePacket() [2/4]

std::shared_ptr< const Packet > regina::Packet::nextTreePacket ( ) const

inherited

Finds the next packet after this in a complete depth-first iteration of the entire tree structure to which this packet belongs.

Note that this packet need not be the tree matriarch.

A parent packet is always reached before its children. The tree matriarch will be the first packet visited in a complete depth-first iteration.

Returns

the next packet, or null if this is the last packet in such an iteration.

nextTreePacket() [3/4]

std::shared_ptr< Packet > regina::Packet::nextTreePacket ( PacketType  type )

inlineinherited

Finds the next packet after this of the requested type in a complete depth-first iteration of the entire tree structure.

Note that this packet need not be the tree matriarch. The order of tree searching is described in firstTreePacket().

Parameters

type	the type of packet to search for.

Returns

the next such packet, or null if this is the last packet of the requested type in such an iteration.

nextTreePacket() [4/4]

std::shared_ptr< const Packet > regina::Packet::nextTreePacket ( PacketType  type ) const

inlineinherited

Finds the next packet after this of the requested type in a complete depth-first iteration of the entire tree structure.

Note that this packet need not be the tree matriarch. The order of tree searching is described in firstTreePacket().

Parameters

type	the type of packet to search for.

Returns

the next such packet, or null if this is the last packet of the requested type in such an iteration.

operator!=()

bool regina::Script::operator!= ( const Script &  other ) const

inline

Determines if this and the given script are not identical.

Here identical means that both scripts contain exactly the same text, and they have the same set of variables. For two variables to be considered the same, they must have the same variable name, and their values must be either both null or both pointers to the same packet.

Parameters

other

the script to compare with this.

Returns

true if and only if this and the given script are not identical.

operator=()

Script & regina::Script::operator=

(

const Script &

src

)

Sets this to be a copy of the given script packet.

Like all packet types, this only copies the script content, not the packet infrastructure (e.g., it will not copy the packet label, or change this packet's location in any packet tree).

Parameters

src	the script packet whose contents should be copied.

Returns

a reference to this packet.

operator==()

bool regina::Script::operator==

(

const Script &

other

)

const

Determines if this and the given script are identical.

Here identical means that both scripts contain exactly the same text, and they have the same set of variables. For two variables to be considered the same, they must have the same variable name, and their values must be either both null or both pointers to the same packet.

Parameters

other

the script to compare with this.

Returns

true if and only if this and the given script are identical.

parent()

std::shared_ptr< Packet > regina::Packet::parent ( ) const

inlineinherited

Determines the parent packet in the tree structure.

This routine takes small constant time.

Returns

the parent packet, or null if there is none.

prepend()

void regina::Packet::prepend ( std::shared_ptr< Packet >  child )

inherited

Inserts the given packet as the first child of this packet.

This packet will take ownership of child, in the sense that every parent packet stores (either directly or indirectly) a shared_ptr to every one of its descendants in the packet tree.

In Regina 7.0 and earlier, this routine was called insertChildFirst().

This routine takes small constant time.

Precondition

The given child has no parent packet.

This packet is not a descendant of the given child.

Exceptions

InvalidArgument

The argument child already has a parent packet. Note that, although this tests one of our preconditions, there are other preconditions that are not tested, and for which no exceptions are thrown.

Parameters

child

the child to insert.

prevSibling()

std::shared_ptr< Packet > regina::Packet::prevSibling ( ) const

inlineinherited

Determines the previous sibling of this packet in the tree structure.

This is the child of the parent that precedes this packet.

This routine takes small constant time.

Returns

the previous sibling of this packet, or null if there is none.

removeAllTags()

void regina::Packet::removeAllTags ( )

inherited

Removes all associated tags from this packet.

Each packet can have an arbitrary set of string tags associated with it. The tags are not used by this calculation engine; the feature is provided for whatever use a developer or user chooses to make of it.

Tags are case-sensitive. Tags associated with a single packet must be distinct, i.e., a particular tag cannot be associated more than once with the same packet.

removeAllVariables()

void regina::Script::removeAllVariables ( )

inline

Removes all variables associated with this script.

removeTag()

bool regina::Packet::removeTag ( const std::string &  tag )

inherited

Removes the association of the given tag with this packet.

Each packet can have an arbitrary set of string tags associated with it. The tags are not used by this calculation engine; the feature is provided for whatever use a developer or user chooses to make of it.

Tags are case-sensitive. Tags associated with a single packet must be distinct, i.e., a particular tag cannot be associated more than once with the same packet.

Parameters

tag	the tag to remove.

Returns

true if the given tag was removed, or false if the given tag was not actually associated with this packet.

removeVariable() [1/2]

void regina::Script::removeVariable

(

const std::string &

name

)

Removes the variable stored with the given name.

If no variable is stored with the given name, this routine will do nothing.

Warning

This may change the indices of other variables, since (at present) variables are kept stored in sorted order by name.

Parameters

name	the name of the variable to remove; note that names are case sensitive.

removeVariable() [2/2]

void regina::Script::removeVariable

(

size_t

index

)

Removes the variable stored at the given index.

Warning

This may change the indices of other variables, since (at present) variables are kept stored in sorted order by name.

Parameters

index

the index of the variable to remove; this must be between 0 and countVariables()-1 inclusive.

reparent()

void regina::Packet::reparent ( const std::shared_ptr< Packet > &  newParent, bool  first = false  )

inherited

Cuts this packet away from its parent in the tree structure, and inserts it as a child of the given packet instead.

This routine is essentially a combination of makeOrphan() followed by either prepend() or append().

Even if you are not holding a shared_ptr to this packet yourself, this routine is still safe to use: it will maintain a shared_ptr as a "guard" so that this packet is not inadvertently destroyed during the transfer.

You may pass newParent as null, in which case this routine behaves in the same way as makeOrphan() (and is similarly safe to use even if there are no other shared pointers to this packet).

This routine takes small constant time. It is safe to use regardless of whether this packet currently has a parent or not.

If you wish to reparent all of the children of a given packet, see transferChildren() instead.

Precondition

The given parent is not a descendant of this packet.

Parameters

newParent	the new parent of this packet, i.e., the packet beneath which this packet will be inserted.
first	true if this packet should be inserted as the first child of the given parent, or false (the default) if it should be inserted as the last child.

root()

std::shared_ptr< Packet > regina::Packet::root ( ) const

inherited

Determines the root of the tree to which this packet belongs.

Returns

the matriarch of the packet tree.

samePacket()

bool regina::Packet::samePacket ( const Packet &  other ) const

inlineinherited

Determines whether this and the given object refer to the same packet.

This is exactly the same as testing whether the underlying Packet pointers are equal, and so this routine is unnecessary for C++ users.

Instead, this routine is designed for Python users, since:

• the Python keyword is will not work, because there could be many different Python wrappers all pointing to the same C++ object;
• the Python equality test (==) will not work, since as of Regina 7.0 this compares objects by value (i.e., it tests whether their contents are equal).

A use case for this function could be (for example) iterating through a packet tree and identifying when a particular known packet has been found.

Parameters

other

the packet to compare with this.

Returns

true if and only if this and the given object refer to the same underlying packet.

save() [1/2]

bool regina::Packet::save ( const char *  filename, bool  compressed = true, FileFormat  format = REGINA_CURRENT_FILE_FORMAT  ) const

inherited

Saves the subtree rooted at this packet to the given Regina data file, using Regina's native XML file format.

The XML file may be optionally compressed (Regina can happily read both compressed and uncompressed XML).

This is the preferred way of saving a Regina data file. Typically this will be called from the root of the packet tree, which will save the entire packet tree to file.

Precondition

The given packet does not depend on its parent.

Internationalisation

This routine makes no assumptions about the character encoding used in the given file name, and simply passes it through unchanged to low-level C/C++ file I/O routines. The contents of the file will be written using UTF-8.

Parameters

filename	the pathname of the file to write to.
compressed	true if the XML data should be compressed, or false if it should be written as plain text.
format	indicates which of Regina's XML file formats to write. You should use the default (REGINA_CURRENT_FILE_FORMAT) unless you need your file to be readable by older versions of Regina. This must not be REGINA_BINARY_GEN_1, which is no longer supported.

Returns

true if and only if the file was successfully written.

save() [2/2]

bool regina::Packet::save ( std::ostream &  s, bool  compressed = true, FileFormat  format = REGINA_CURRENT_FILE_FORMAT  ) const

inherited

Writes the subtree rooted at this packet to the given output stream, in the format of a Regina XML data file.

The data file may be optionally compressed (Regina can happily read both compressed and uncompressed XML).

Typically this will be called from the root of the packet tree, which will write the entire packet tree to the given output stream.

Precondition

The given stream is open for writing.

The given packet does not depend on its parent.

Python

Not present. This is not available in Python to avoid confusion with the filename-based save(). However, if you wish to write a Regina XML data file directly to an open Python file, you can still use writeXMLFile() for this.

Parameters

s	the output stream to which to write.
compressed	true if the XML data should be compressed, or false if it should be written as plain text.
format	indicates which of Regina's XML file formats to write. You should use the default (REGINA_CURRENT_FILE_FORMAT) unless you need your file to be readable by older versions of Regina. This must not be REGINA_BINARY_GEN_1, which is no longer supported.

Returns

true if and only if the data was successfully written.

setLabel()

void regina::Packet::setLabel ( const std::string &  label )

inherited

Sets the label associated with this individual packet.

Parameters

label

the new label to give this packet.

setText()

void regina::Script::setText ( const std::string &  newText )

inline

Replaces the complete text of this script with the given string.

Variables are not considered part of the text; you can get and set them through other member functions (see below).

Parameters

newText

the new text for this script.

setVariableName()

void regina::Script::setVariableName	(	size_t	index,
		const std::string &	name
	)

Changes the name of an existing variable associated with this script.

Warning

This may change the indices of this and other variables, since (at present) variables are kept stored in sorted order by name.

Parameters

index	the index of the variable whose name should change; this must be between 0 and countVariables()-1 inclusive.
name	the new name to assign to the variable.

setVariableValue()

void regina::Script::setVariableValue	(	size_t	index,
		std::weak_ptr< Packet >	value = {}
	)

Changes the value of an existing variable associated with this script.

Parameters

index	the index of the variable whose value should change; this must be between 0 and countVariables()-1 inclusive.
value	the new value to assign to the variable. This is allowed to be a null pointer, and if the argument is omitted then a null pointer will be used.

sortChildren()

void regina::Packet::sortChildren ( )

inherited

Sorts the immediate children of this packet according to their packet labels.

Note that this routine is not recursive (for instance, grandchildren will not be sorted within each child packet).

This routine takes quadratic time in the number of immediate children (and it's slow quadratic at that).

str()

std::string regina::Output< Packet , false >::str ( ) const

inherited

Returns a short text representation of this object.

This text should be human-readable, should use plain ASCII characters where possible, and should not contain any newlines.

Within these limits, this short text ouptut should be as information-rich as possible, since in most cases this forms the basis for the Python __str__() and __repr__() functions.

Python

The Python "stringification" function __str__() will use precisely this function, and for most classes the Python __repr__() function will incorporate this into its output.

Returns

a short text representation of this object.

swap()

void regina::Script::swap

(

Script &

other

)

Swaps the contents of this and the given script packet.

Like all packet types, this only swaps the script content, not the packet infrastructure (e.g., it will not swap packet labels, or change either packet's location in any packet tree).

Parameters

other

the script packet whose contents should be swapped with this.

swapWithNextSibling()

void regina::Packet::swapWithNextSibling ( )

inherited

Swaps this packet with its next sibling in the sequence of children beneath their common parent packet.

Calling this routine is equivalent to calling moveDown().

This routine takes small constant time.

If this packet has no next sibling then this routine safely does nothing.

tags()

const std::set< std::string > & regina::Packet::tags ( ) const

inlineinherited

Returns the set of all tags associated with this packet.

Each packet can have an arbitrary set of string tags associated with it. The tags are not used by this calculation engine; the feature is provided for whatever use a developer or user chooses to make of it.

Tags are case-sensitive. Tags associated with a single packet must be distinct, i.e., a particular tag cannot be associated more than once with the same packet.

Python

This routine returns a python set.

Returns

the set of all tags associated with this packet.

text()

const std::string & regina::Script::text ( ) const

inline

Returns the complete text of this script.

Variables are not considered part of the text; you can get and set them through other member functions (see below).

Returns

the complete text of this script.

totalTreeSize()

size_t regina::Packet::totalTreeSize ( ) const

inherited

Determines the total number of packets in the tree or subtree for which this packet is matriarch.

This packet is included in the count.

Returns

the total tree or subtree size.

transferChildren()

void regina::Packet::transferChildren ( const std::shared_ptr< Packet > &  newParent )

inherited

Cuts all of this packet's children out of the packet tree, and reinserts them as children of the given packet instead.

The children of this packet will be appended to the end of the new parent's child list, in the same order as they were previously.

This is equivalent to calling reparent() on each child, but should be somewhat faster if there are many children to move.

Even if you are not holding a shared_ptr to any of this packet's children, this routine is still safe to use: it will ensure there is always some shared_ptr to guard against any children being inadvertently destroyed during the transfer.

You may pass newParent as null, in which case this routine is equivalent to calling makeOrphan() on each child (and is similarly safe to use even if there are no other shared pointers to this packet).

Precondition

The given parent is not a descendant of this packet.

Parameters

newParent

the new parent beneath which the children will be inserted.

type()

virtual PacketType regina::Packet::type ( ) const

pure virtualinherited

Returns the unique integer ID representing this type of packet.

This is the same for all packets of this class.

Returns

the packet type ID.

typeName()

virtual std::string regina::Packet::typeName ( ) const

pure virtualinherited

Returns an English name for this type of packet.

An example is Triangulation3. This is the same for all packets of this class.

Returns

the packet type name.

unlisten()

bool regina::Packet::unlisten ( PacketListener *  listener )

inherited

Unregisters the given packet listener so that it no longer listens for events on this packet.

See the PacketListener class notes for details.

Parameters

listener

the listener to unregister.

Returns

true if the given listener was successfully unregistered, or false if the given listener was not registered in the first place.

unlistenVariables()

void regina::Script::unlistenVariables ( PacketListener *  listener )

inline

Deregisters the given packet listener from listening for events on all of packets identified by this script's variables.

Like listenVariables(), this is a one-off operation: it will not make any further adjustments if the script variables should change later on.

This routine is safe to call if some variables have null values, and/or if the same packet is identified by multiple variables.

Parameters

listener

the listener to deregister from all packets identified by the script variables.

utf8()

std::string regina::Output< Packet , false >::utf8 ( ) const

inherited

Returns a short text representation of this object using unicode characters.

Like str(), this text should be human-readable, should not contain any newlines, and (within these constraints) should be as information-rich as is reasonable.

Unlike str(), this function may use unicode characters to make the output more pleasant to read. The string that is returned will be encoded in UTF-8.

Returns

a short text representation of this object.

variableIndex()

long regina::Script::variableIndex

(

const std::string &

name

)

const

Returns the index of the variable stored with the given name.

Parameters

name	the name of the requested variable; note that names are case sensitive.

Returns

the index of the requested variable as an integer between 0 and countVariables()-1 inclusive, or -1 if there is no variable with the given name.

variableName()

const std::string & regina::Script::variableName

(

size_t

index

)

const

Returns the name of the requested variable associated with this script.

Parameters

index

the index of the requested variable; this must be between 0 and countVariables()-1 inclusive.

Returns

the name of the requested variable.

variableValue() [1/2]

std::shared_ptr< Packet > regina::Script::variableValue

(

const std::string &

name

)

const

Returns the value of the variable stored with the given name.

Variables may take the value null.

If no variable is stored with the given name, then null will likewise be returned.

Parameters

name	the name of the requested variable; note that names are case sensitive.

Returns

the value of the requested variable.

variableValue() [2/2]

std::shared_ptr< Packet > regina::Script::variableValue

(

size_t

index

)

const

Returns the value of the requested variable associated with this script.

Variables may take the value null.

Parameters

index

the index of the requested variable; this must be between 0 and countVariables()-1 inclusive.

Returns

the value of the requested variable.

writeTextLong()

void regina::Script::writeTextLong ( std::ostream &  out ) const

overridevirtual

Writes a detailed text representation of this object to the given output stream.

This may be reimplemented by subclasses, but the parent Packet class offers a reasonable default implementation.

Python

Not present. Use detail() instead.

Parameters

out	the output stream to which to write.

Reimplemented from regina::Packet.

writeTextShort()

void regina::Script::writeTextShort ( std::ostream &  out ) const

overridevirtual

Writes a short text representation of this object to the given output stream.

This must be reimplemented by subclasses.

Python

Not present. Use str() instead.

Parameters

out	the output stream to which to write.

Implements regina::Packet.

writeXMLAnon()

void regina::Packet::writeXMLAnon ( std::ostream &  out, FileFormat  format, PacketRefs &  refs, const Packet &  p  ) const

protectedinherited

Writes the given packet inside its own anonymous block.

This could (for example) be called as the first step in writeXMLPacketData() if the packet needs some dependency p to have been explicitly written to file and this has not been done yet.

This function simply creates an anon XML block, and within it calls p.writeXMLPacketData() with the anon argument set to true.

Parameters

out	the output stream to which the anonymous block should be written.
format	indicates which of Regina's XML file formats to write.
refs	manages the necessary references between packets in the XML file; see the PacketRefs documentation for details.
p	the packet to write inside the anonymous block.

writeXMLFile()

void regina::Packet::writeXMLFile ( std::ostream &  out, FileFormat  format = REGINA_CURRENT_FILE_FORMAT  ) const

inherited

Writes the subtree rooted at this packet to the given output stream in Regina's native XML file format.

Ths is similar to calling save(), except that (i) the user has a more flexible choice of output stream, and (ii) the XML will always be written in plain text (i.e., it will not be compressed).

If you simply wish to save your data to a file on the filesystem, you should call save() instead.

Typically this will be called from the root of the packet tree, which will write the entire packet tree to the output stream.

Python

The argument out should be an open Python file object.

Parameters

out	the output stream to which the XML data file should be written.
format	indicates which of Regina's XML file formats to write. You should use the default (REGINA_CURRENT_FILE_FORMAT) unless you need your file to be readable by older versions of Regina. This must not be REGINA_BINARY_GEN_1, which is no longer supported.

writeXMLFooter()

void regina::Packet::writeXMLFooter ( std::ostream &  out, const char *  element, FileFormat  format  ) const

protectedinherited

Writes the closing XML tag for this packet.

This is typically called at the end of writeXMLPacketData().

There will be no whitespace before the closing XML tag. The tag will be followed by a newline.

Parameters

out	the output stream to which the closing XML tag should be written.
element	the name of the XML tag. If we are writing to the REGINA_XML_GEN_2 format, then this will be ignored (and may be null), and the tag name packet will be used instead.
format	indicates which of Regina's XML file formats to write.

writeXMLHeader()

template<typename... Args>

void regina::Packet::writeXMLHeader ( std::ostream &  out, const char *  element, FileFormat  format, bool  anon, PacketRefs &  refs, bool  newline, std::pair< const char *, Args >...  attr  ) const

protectedinherited

Writes the opening XML tag for this packet.

This is typically called at the beginning of writeXMLPacketData().

The generic packet attributes (such as label, id if required, and type / typeid if we are writing to the second-generation format REGINA_XML_GEN_2) will be included.

If we are writing to the third-generation file format or newer, then any additional attributes specified in attr will also be included. If we are writing to the second-generation format REGINA_XML_GEN_2, then attr will be ignored.

If this packet appears as a key in the refs map, or if the anon argument indicates that we are in an anonymous block, then this routine will set refs[this] as true to record that this packet is now being written to XML.

Parameters

out	the output stream to which the opening XML tag should be written.
element	the name of the XML tag. If we are writing to the REGINA_XML_GEN_2 format, then this will be ignored (and may be null), and the tag name packet will be used instead.
format	indicates which of Regina's XML file formats to write.
anon	true if this packet is being written within an anonymous block. If so, then the packet ID will always be written.
refs	manages the necessary references between packets in the XML file; see the PacketRefs documentation for details.
newline	indicates whether the opening XML tag should be followed by a newline. Normally this would be true, but if you need to avoid whitespace between the opening XML tag and the packet contents then you should pass false instead.
attr	any additional attributes to write to the XML tag; each attribute should a pair of the form (attribute, value). When writing to the REGINA_XML_GEN_2 format, this will be ignored.

writeXMLPacketData()

void regina::Script::writeXMLPacketData ( std::ostream &  out, FileFormat  format, bool  anon, PacketRefs &  refs  ) const

overrideprotectedvirtual

Writes a chunk of XML containing the full subtree with this packet as matriarch.

This should contain:

• any anonymous packets that need to be written before this packet (but first check refs to ensure these packets have not already been written);
• the packet opening XML tag;
• the packet contents;
• any packet tags and/or child packets (but only if we are not inside an anonymous block);
• a closing XML tag and a final newline.

For native packet types, these five stages are typically implemented using:

• optional calls to writeXMLAnon();
• a single call to writeXMLHeader();
• customised output;
• a single call to writeXMLTreeData(), if anon is false;
• a single call to writeXMLFooter().

For wrapped packet types that use a PacketOf<Held> wrapper, you should instead just specialise the routines from XMLWriter<Held>. The PacketOf wrapper will take care of the tree-specific code (in particular, it will handle the calls to writeXMLAnon() and writeXMLTreeData()).

The output from this routine is only a piece of XML; it should not be used as a complete XML file. For a complete XML file, see routine writeXMLFile() instead.

Parameters

out	the output stream to which the XML should be written.
format	indicates which of Regina's XML file formats to write.
anon	true if this packet is being written within an anonymous block. If so, then the packet ID must be included, and any packet tags and/or child packets must be excluded.
refs	manages the necessary references between packets in the XML file; see the PacketRefs documentation for details.

Implements regina::Packet.

writeXMLTreeData()

void regina::Packet::writeXMLTreeData ( std::ostream &  out, FileFormat  format, PacketRefs &  refs  ) const

protectedinherited

Writes any generic XML sub-elements for this packet that come from the packet tree.

This is typically called towards the end of writeXMLPacketData(), just before the final call to writeXMLFooter().

The generic sub-elements include Regina's packet tags, as well as any child packets in the packet tree.

There will be no whitespace before the first sub-element (and so if there are no sub-elements at all then this routine will output nothing).

Precondition

This packet is not contained within an anonymous block.

Parameters

out	the output stream to which the closing XML tag should be written.
format	indicates which of Regina's XML file formats to write.
refs	manages the necessary references between packets in the XML file; see the PacketRefs documentation for details.

---

The documentation for this class was generated from the following file:

• packet/script.h