ExternalVariable represent any access to external (custom) data, typically associated with the '$' symbol syntax. Note that the AST does not store any additional information on the given external other than its name and type, which together form a unique external identifier known as the ExternalVariable 'token'. This token is used by the compiler to map user provided values to these external values. More...

#include <openvdb_ax/ast/AST.h>

Inherits Variable.

Public Types
using	UniquePtr = std::unique_ptr< ExternalVariable >

enum	NodeType { TreeNode, StatementListNode, BlockNode, ConditionalStatementNode, CommaOperatorNode, LoopNode, KeywordNode, AssignExpressionNode, CrementNode, UnaryOperatorNode, BinaryOperatorNode, TernaryOperatorNode, CastNode, AttributeNode, FunctionCallNode, ExternalVariableNode, DeclareLocalNode, ArrayPackNode, ArrayUnpackNode, LocalNode, ValueBoolNode, ValueInt16Node, ValueInt32Node, ValueInt64Node, ValueFloatNode, ValueDoubleNode, ValueStrNode }
	An enumerated list of node types for all concrete node types. These can be used for faster evaluation of a given concrete node using the virtual function table via Node::nodetype() rather than performing a dynamic_cast/calling Node::isType. More...

using	Ptr = std::shared_ptr< Node >

Public Member Functions
	ExternalVariable (const std::string &name, const tokens::CoreType type)
	Construct a new ExternalVariable with a given name and type. More...

	ExternalVariable (const std::string &name, const std::string &token)
	Construct a new ExternalVariable with a given name and type/token string, delegating construction to the above ExternalVariable constructor. More...

	ExternalVariable (const ExternalVariable &other)
	Deep copy constructor for a ExternalVariable. More...

	~ExternalVariable () override=default

ExternalVariable *	copy () const override final
	The deep copy method for a Node. More...

NodeType	nodetype () const override
	Virtual method for accessing node type information. More...

const char *	nodename () const override
	Virtual method for accessing node name information. More...

const char *	subname () const override
	Virtual method for accessing node name information. More...

const Variable *	basetype () const override
	Virtual method for accessing a node's base class. Note that if this is called explicitly on an instance of ast::Node (the top most base class) a nullptr is returned. This is primarily used by the Visitor to support hierarchical visits. More...

tokens::CoreType	type () const
	Access the type that was used to access this external variable. More...

std::string	typestr () const
	Get the access type as a front end AX type/token string. More...

const std::string	tokenname () const
	Construct and return the full external token identifier. See ExternalVariable::tokenFromNameType. More...

size_t	children () const override
	Virtual method for accessing child information. Returns the number of children a given AST node owns. More...

const Node *	child (const size_t) const override
	Virtual method for accessing child information. Returns a const pointer to a child node at the given index. If the index is out of range, a nullptr is returned. More...

const std::string &	name () const

Name/Type
template<typename NodeT >
bool	isType () const
	Query whether or not this node is of a specific (derived) type. This method should be used to check if a node is of a particular abstract type. When checking concrete types, it's generally more efficient to check the return value of Node::nodetype() More...

Child Queries
int64_t	childidx () const
	Returns the child index of this node in relation to its parent, or -1 if no valid index is found (usually representing the top most node (i.e. Tree) More...

Replacement
bool	replace (Node *node)
	In place replacement. Attempts to replace this node at its specific location within its Abstract Syntax Tree. On a successful replacement, this node is destroyed, the provided node is inserted in its place and ownership is transferred to the parent node. No further calls to this node can be made on successful replacements. More...

virtual bool	replacechild (const size_t index, Node *node)
	Virtual method that attempted to replace a child at a given index with a provided node type. More...

Parent
const Node *	parent () const
	Access a const pointer to this nodes parent. More...

void	setParent (Node *parent)
	Set this node's parent. This is used during construction of an AST and should not be used. More...

Static Public Member Functions
static char	symbolseparator ()
	Static method returning the symbol associated with an ExternalVariable access as defined by AX Grammar. More...

static std::string	tokenFromNameType (const std::string &name, const tokens::CoreType type)
	Static method returning the full unique external token identifier by consolidating its name and type such that token = tokenstr + '$' + name, where tokenstr is the AX type token as a string, converted from the provided CoreType. More...

static bool	nametypeFromToken (const std::string &token, std::string name, std::string type)
	Static method which splits a valid external token into its name and type counterparts. If the token cannot be split, neither name or type are updated and false is returned. More...

Detailed Description

ExternalVariable represent any access to external (custom) data, typically associated with the '$' symbol syntax. Note that the AST does not store any additional information on the given external other than its name and type, which together form a unique external identifier known as the ExternalVariable 'token'. This token is used by the compiler to map user provided values to these external values.

Note: The Attribute AST node works in a similar way; An ExternalVariable is a complete "leaf-level" AST node. It has no children and nothing derives from it.

Member Typedef Documentation

using Ptr = std::shared_ptr<Node>

inherited

using UniquePtr = std::unique_ptr<ExternalVariable>

Member Enumeration Documentation

enum NodeType

inherited

An enumerated list of node types for all concrete node types. These can be used for faster evaluation of a given concrete node using the virtual function table via Node::nodetype() rather than performing a dynamic_cast/calling Node::isType.

Note: This is sometimes referred to as "manual RTTI". We use this technique combine with single dispatch due to opting for CRTP on the main visitor and no templated virtual method support in C++. i.e. no way to double dispatch: visit<template T>(Visitor<T>*); Abstract (pure-virtual) nodes are not listed here. Node::isType should be used to determine if a node is of a given abstract type.

Enumerator
TreeNode
StatementListNode
BlockNode
ConditionalStatementNode
CommaOperatorNode
LoopNode
KeywordNode
AssignExpressionNode
CrementNode
UnaryOperatorNode
BinaryOperatorNode
TernaryOperatorNode
CastNode
AttributeNode
FunctionCallNode
ExternalVariableNode
DeclareLocalNode
ArrayPackNode
ArrayUnpackNode
LocalNode
ValueBoolNode
ValueInt16Node
ValueInt32Node
ValueInt64Node
ValueFloatNode
ValueDoubleNode
ValueStrNode

Constructor & Destructor Documentation

ExternalVariable	(	const std::string &	name,
		const tokens::CoreType	type
	)

inline

Construct a new ExternalVariable with a given name and type.

Parameters

name	The name of the attribute
type	The type of the attribute

ExternalVariable	(	const std::string &	name,
		const std::string &	token
	)

inline

Construct a new ExternalVariable with a given name and type/token string, delegating construction to the above ExternalVariable constructor.

Parameters

name	The name of the attribute
token	The type/token string of the attribute

ExternalVariable ( const ExternalVariable & other )

inline

Deep copy constructor for a ExternalVariable.

Note: No parent information needs updating as an ExternalVariable is a "leaf level" node (contains no children)

Parameters

other A const reference to another ExternalVariable to deep copy

~ExternalVariable ( )

overridedefault

Member Function Documentation

const Variable* basetype ( ) const

inlineoverridevirtual

Virtual method for accessing a node's base class. Note that if this is called explicitly on an instance of ast::Node (the top most base class) a nullptr is returned. This is primarily used by the Visitor to support hierarchical visits.

Reimplemented from Variable.

const Node* child ( const size_t index ) const

inlineoverridevirtualinherited

Virtual method for accessing child information. Returns a const pointer to a child node at the given index. If the index is out of range, a nullptr is returned.

Note: This may still return a nullptr even if the given index is valid if the child node has not been created.

Parameters

index The child index to query

Returns: A Pointer to the child node, or a nullptr if none exists.

Implements Node.

int64_t childidx ( ) const

inlineinherited

Returns the child index of this node in relation to its parent, or -1 if no valid index is found (usually representing the top most node (i.e. Tree)

Returns: The child index of this node

size_t children ( ) const

inlineoverridevirtualinherited

Virtual method for accessing child information. Returns the number of children a given AST node owns.

Returns: The number of children this node owns.

Implements Node.

ExternalVariable* copy ( ) const

inlinefinaloverridevirtual

The deep copy method for a Node.

Implements Variable.

bool isType ( ) const

inlineinherited

Query whether or not this node is of a specific (derived) type. This method should be used to check if a node is of a particular abstract type. When checking concrete types, it's generally more efficient to check the return value of Node::nodetype()

Template Parameters

NodeT The node type to query against.

Returns: True if this node is of the given type, false otherwise.

const std::string& name ( ) const

inlineinherited

static bool nametypeFromToken	(	const std::string &	token,
		std::string *	name,
		std::string *	type
	)

inlinestatic

Static method which splits a valid external token into its name and type counterparts. If the token cannot be split, neither name or type are updated and false is returned.

Parameters

token	The token to split.
name	Set to the second part of the external token, representing the name. If a nullptr, it is ignored
type	Set to the first part of the external token, representing the type. If a nullptr, it is ignored. Note that this can be empty if the external token has an inferred type or a single character.

Returns: True if the provided external token could be split

const char* nodename ( ) const

inlineoverridevirtual

Virtual method for accessing node name information.

Implements Node.

NodeType nodetype ( ) const

inlineoverridevirtual

Virtual method for accessing node type information.

Implements Node.

const Node* parent ( ) const

inlineinherited

Access a const pointer to this nodes parent.

Note: Can be a nullptr if this is the top most node in an AST (usually a Tree)

Returns: A const pointer to this node's parent node

bool replace ( Node * node )

inlineinherited

In place replacement. Attempts to replace this node at its specific location within its Abstract Syntax Tree. On a successful replacement, this node is destroyed, the provided node is inserted in its place and ownership is transferred to the parent node. No further calls to this node can be made on successful replacements.

Note: A replacement will fail if this node is the top most node within an AST hierarchy or if the provided node type is not a compatible type for the required abstract storage. For example, if this node is an Attribute being held on a BinaryOperator, only concrete nodes derived from an Expression can be used as a replacement.; This method will dynamic_cast the provided node to check to see if it's a compatible type.

Parameters

node	The node to insert on a successful replacement.

Returns: True if the replacement was successful, resulting in destruction of this class and ownership transferal of the provided node. False otherwise, where this and the provided node are unchanged.

bool replacechild	(	const size_t	index,
		Node *	node
	)

inlinevirtualinherited

Virtual method that attempted to replace a child at a given index with a provided node type.

Note: See Node::replace for a more detailed description

Parameters

index	The child index where a replacement should be attempted
node	The node to insert on a successful replacement.

Returns: True if the replacement was successful, false otherwise

Reimplemented in DeclareLocal, ArrayPack, ArrayUnpack, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Block, and StatementList.

void setParent ( Node * parent )

inlineinherited

Set this node's parent. This is used during construction of an AST and should not be used.

Parameters

parent The parent to set

const char* subname ( ) const

inlineoverridevirtual

Virtual method for accessing node name information.

Implements Node.

static char symbolseparator ( )

inlinestatic

Static method returning the symbol associated with an ExternalVariable access as defined by AX Grammar.

Returns: The '$' character as a char

static std::string tokenFromNameType	(	const std::string &	name,
		const tokens::CoreType	type
	)

inlinestatic

Static method returning the full unique external token identifier by consolidating its name and type such that token = tokenstr + '$' + name, where tokenstr is the AX type token as a string, converted from the provided CoreType.

Note: This identifier is unique for accesses to the same external; Due to inferred and single character accesses in AX, this return value does not necessarily represent the original syntax used to access this external. For example, v$data will be stored and returned as vec3f$data.

Parameters

name	The name of the external
type	The CoreType of the external

Returns: A string representing the external token.

const std::string tokenname ( ) const

inline

Construct and return the full external token identifier. See ExternalVariable::tokenFromNameType.

Returns: A string representing the external variable token.

tokens::CoreType type ( ) const

inline

Access the type that was used to access this external variable.

Returns: The type used to access this external as a tokens::CoreType

std::string typestr ( ) const

inline

Get the access type as a front end AX type/token string.

Note: This returns the associated token to the type, not necessarily equal to the OpenVDB type string

Returns: A string representing the type/token

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation