OpenVDB  8.1.1
Public Types | Public Member Functions | Static Public Attributes | List of all members
Value< T > Struct Template Reference

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 <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 ValueBasebasetype () 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...
 
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 Nodechild (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 Nodeparent () 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::v8_1::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
otherA 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
indexThe 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
NodeTThe 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
nodeThe 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
indexThe child index where a replacement should be attempted
nodeThe 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
parentThe 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

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