Node Struct Reference

The base abstract node which determines the interface and required methods for all derived concrete nodes which comprise a valid AST. More...

#include <openvdb_ax/ast/AST.h>

Inherited by Statement, and Tree.

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

Public Member Functions
	Node ()=default
virtual	~Node ()=default
virtual Node *	copy () const =0
	The deep copy method for a Node. More...
Name/Type
virtual NodeType	nodetype () const =0
	Virtual method for accessing node type information. More...
virtual const char *	nodename () const =0
	Virtual method for accessing node name information. More...
virtual const char *	subname () const =0
	Virtual method for accessing node name information. More...
virtual const Node *	basetype () const
	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...
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
virtual size_t	children () const =0
	Virtual method for accessing child information. Returns the number of children a given AST node owns. More...
virtual const Node *	child (const size_t index) const =0
	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...
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...

Detailed Description

The base abstract node which determines the interface and required methods for all derived concrete nodes which comprise a valid AST.

A reference list of all abstract and concrete AST nodes in hierarchical order (non-linear) Abstract nodes:

• Node
• Statement
• Expression
• Variable
• ValueBase

Concrete nodes:

• Tree
• StatementList
• Block
• Loop
• Keyword
• ConditionalStatement
• CommaOperator
• BinaryOperator
• TernaryOperator
• AssignExpression
• Crement
• UnaryOperator
• Cast
• FunctionCall
• ArrayUnpack
• ArrayPack
• Attribute
• ExternalVariable
• DeclareLocal
• Local
• Value<double/float/int32_t/int16_t/int64_t/bool>
• Value<std::string>

  Note

  All AST nodes share a few common characteristics. All constructors typically take pointers to the abstract (pure-virtual) node types and assume ownership of this data on successful construction. Deep copy methods propagate down through all children of a given AST node but have the unique behavior of ensuring parent data is updated to the newly created parent nodes. Due to this behavior and the fact that most nodes store unique pointers to other nodes, we've omitted comparison and equality operators.

Member Typedef Documentation

using Ptr = std::shared_ptr<Node>

using UniquePtr = std::unique_ptr<Node>

Member Enumeration Documentation

enum NodeType

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

Node ( )

default

virtual ~Node ( )

virtualdefault

Member Function Documentation

virtual const Node* basetype ( ) const

inlinevirtual

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.

Returns

Returns the current node as its base class type.

Reimplemented in Value< std::string >, Value< T >, DeclareLocal, Local, ExternalVariable, Attribute, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, StatementList, ValueBase, Variable, Expression, and Statement.

virtual const Node* child ( const size_t  index ) const

pure virtual

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.

Implemented in DeclareLocal, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, StatementList, ValueBase, and Variable.

int64_t childidx ( ) const

inline

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

virtual size_t children ( ) const

pure virtual

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

Returns

The number of children this node owns.

Implemented in DeclareLocal, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, StatementList, ValueBase, and Variable.

virtual Node* copy ( ) const

pure virtual

The deep copy method for a Node.

Returns

A deep copy of the current node and all its children

Implemented in Value< std::string >, Value< T >, DeclareLocal, Local, ExternalVariable, Attribute, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, StatementList, ValueBase, Variable, Expression, and Statement.

bool isType ( ) const

inline

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.

virtual const char* nodename ( ) const

pure virtual

Virtual method for accessing node name information.

Returns

Returns the node class name

Implemented in Value< std::string >, Value< T >, DeclareLocal, Local, ExternalVariable, Attribute, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, and StatementList.

virtual NodeType nodetype ( ) const

pure virtual

Virtual method for accessing node type information.

Note

This method should be used when querying a concrete nodes type.

Returns

Returns the enumerated node type from the NodeType list

Implemented in Value< std::string >, Value< T >, DeclareLocal, Local, ExternalVariable, Attribute, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, and StatementList.

const Node* parent ( ) const

inline

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 )

inline

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  )

inlinevirtual

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 )

inline

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

Parameters

parent

The parent to set

virtual const char* subname ( ) const

pure virtual

Virtual method for accessing node name information.

Returns

Returns the short node class name

Implemented in Value< std::string >, Value< T >, DeclareLocal, Local, ExternalVariable, Attribute, ArrayPack, ArrayUnpack, Keyword, FunctionCall, Cast, UnaryOperator, Crement, AssignExpression, TernaryOperator, BinaryOperator, ConditionalStatement, Loop, CommaOperator, Tree, Block, and StatementList.