A Value (literal) AST node holds either literal text or absolute value information on all numerical, string and boolean constants. A single instance of a Value is templated on the requested scalar, boolean or string type. If scalar or boolean value is constructed from a string (as typically is the case in the parser), the value is automatically converted to its numerical representation. If this fails, the original text is stored instead. More...

#include <openvdb_ax/ast/AST.h>

Inherits ValueBase.

Public Types
using	UniquePtr = std::unique_ptr< Value< T >>

using	Type = T

using	ContainerType = typename std::conditional< std::is_integral< T >::value, uint64_t, T >::type
	Integers and Floats store their value as ContainerType, which is guaranteed to be at least large enough to represent the maximum possible supported type for the requested precision. More...

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
	Value (const ContainerType value)
	Directly construct a Value from a source integer, float or boolean, guaranteeing valid construction. Note that the provided argument should not be negative. More...

	Value (const Value< T > &other)
	Deep copy constructor for a Value. More...

	~Value () override=default

Value< Type > *	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 ValueBase *	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...

ContainerType	asContainerType () const
	Access the value as its stored type. More...

T	value () const
	Access the value as its requested (templated) type. 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...

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 Attributes
static constexpr bool	IsSupported
	The list of supported numerical constants. More...

Detailed Description

template<typename T>
struct openvdb::v12_0::ax::ast::Value< T >

A Value (literal) AST node holds either literal text or absolute value information on all numerical, string and boolean constants. A single instance of a Value is templated on the requested scalar, boolean or string type. If scalar or boolean value is constructed from a string (as typically is the case in the parser), the value is automatically converted to its numerical representation. If this fails, the original text is stored instead.

Note: All numerical values are stored as their highest possible precision type to support overflowing without storing the original string data. The original string data is only required if the value is too large to be stored in these highest precision types (usually a uint64_t for scalars or double for floating points).; Numerical values are guaranteed to be positive (if constructed from the AX parser). Negative values are represented by a combination of a UnaryOperator holding a Value AST node.; Note that Value AST nodes representing strings are specialized and are guranteed to be "well-formed" (there is no numerical conversion); A Value is a complete "leaf-level" AST node. It has no children and nothing derives from it.

Member Typedef Documentation

using ContainerType = typename std::conditional< std::is_integral<T>::value, uint64_t, T>::type

Integers and Floats store their value as ContainerType, which is guaranteed to be at least large enough to represent the maximum possible supported type for the requested precision.

using Ptr = std::shared_ptr<Node>

inherited

using Type = T

using UniquePtr = std::unique_ptr<Value<T>>

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

Value ( const ContainerType value )

inline

Directly construct a Value from a source integer, float or boolean, guaranteeing valid construction. Note that the provided argument should not be negative.

Value ( const Value< T > & other )

inline

Deep copy constructor for a Value.

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

Parameters

other A const reference to another Value to deep copy

~Value ( )

overridedefault

Member Function Documentation

ContainerType asContainerType ( ) const

inline

Access the value as its stored type.

Returns: The value as its stored ContainerType

const ValueBase* 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 ValueBase.

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.

Value<Type>* copy ( ) const

inlinefinaloverridevirtual

The deep copy method for a Node.

Implements ValueBase.

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 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.

T value ( ) const

inline

Access the value as its requested (templated) type.

Returns: The value as its templed type T

Member Data Documentation

constexpr bool IsSupported

static

Initial value:

=
        std::is_same<T, bool>::value ||
        std::is_same<T, int16_t>::value ||
        std::is_same<T, int32_t>::value ||
        std::is_same<T, int64_t>::value ||
        std::is_same<T, float>::value ||
        std::is_same<T, double>::value

The list of supported numerical constants.

Note: Strings are specialized and handled separately

Public Types

Public Member Functions

Static Public Attributes

Detailed Description

template<typename T> struct openvdb::v12_0::ax::ast::Value< T >

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

template<typename T>
struct openvdb::v12_0::ax::ast::Value< T >