OpenVDB  12.0.0
Public Types | Public Member Functions | Static Public Member Functions | List of all members
Attribute Struct Reference

Attributes represent any access to a primitive value, typically associated with the '@' symbol syntax. Note that the AST does not store any additional information on the given attribute other than its name and type, which together form a unique Attribute identifier known as the Attribute 'token'. A 'primitive value' in this instance refers to a value on an OpenVDB Volume or OpenVDB Points tree. More...

#include <openvdb_ax/ast/AST.h>

Inherits Variable.

Public Types

using UniquePtr = std::unique_ptr< Attribute >
 
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

 Attribute (const std::string &name, const tokens::CoreType type, const bool inferred=false)
 Construct a new Attribute with a given name and type. Optionally also mark it as inferred type creation (no type was directly specified) More...
 
 Attribute (const std::string &name, const std::string &token, const bool inferred=false)
 Construct a new Attribute with a given name and type/token string, delegating construction to the above Attribute constructor. More...
 
 Attribute (const Attribute &other)
 Deep copy constructor for a Attribute. More...
 
 ~Attribute () override=default
 
Attributecopy () 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 Variablebasetype () 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...
 
bool inferred () const
 Query whether this attribute was accessed via inferred syntax i.e. @P or @myattribute. More...
 
tokens::CoreType type () const
 Access the type that was used to access this attribute. More...
 
std::string typestr () const
 Get the access type as a front end AX type/token string. More...
 
std::string tokenname () const
 Construct and return the full attribute token identifier. See Attribute::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 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...
 
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 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 Member Functions

static char symbolseparator ()
 Static method returning the symbol associated with an Attribute 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 attribute 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 attribute 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

Attributes represent any access to a primitive value, typically associated with the '@' symbol syntax. Note that the AST does not store any additional information on the given attribute other than its name and type, which together form a unique Attribute identifier known as the Attribute 'token'. A 'primitive value' in this instance refers to a value on an OpenVDB Volume or OpenVDB Points tree.

Note
The ExternalVariable AST node works in a similar way
An Attribute 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<Attribute>

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

Attribute ( const std::string &  name,
const tokens::CoreType  type,
const bool  inferred = false 
)
inline

Construct a new Attribute with a given name and type. Optionally also mark it as inferred type creation (no type was directly specified)

Parameters
nameThe name of the attribute
typeThe type of the attribute
inferredWhether the provided type was directly specified (false).
Attribute ( const std::string &  name,
const std::string &  token,
const bool  inferred = false 
)
inline

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

Parameters
nameThe name of the attribute
tokenThe type/token string of the attribute
inferredWhether the provided type was directly specified (false).
Attribute ( const Attribute other)
inline

Deep copy constructor for a Attribute.

Note
No parent information needs updating as an Attribute is a "leaf level" node (contains no children)
Parameters
otherA const reference to another Attribute to deep copy
~Attribute ( )
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
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.

Attribute* copy ( ) const
inlinefinaloverridevirtual

The deep copy method for a Node.

Implements Variable.

bool inferred ( ) const
inline

Query whether this attribute was accessed via inferred syntax i.e. @P or @myattribute.

Returns
True if inferred syntax was used
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 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 attribute token into its name and type counterparts. If the token cannot be split, neither name or type are updated and false is returned.

Parameters
tokenThe token to split.
nameSet to the second part of the attribute token, representing the name. If a nullptr, it is ignored
typeSet to the first part of the attribute token, representing the type. If a nullptr, it is ignored. Note that this can be empty if the attribute token has an inferred type or a single character.
Returns
True if the provided attribute 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
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.

static char symbolseparator ( )
inlinestatic

Static method returning the symbol associated with an Attribute 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 attribute 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 attribute
Due to inferred and single character accesses in AX, this return value does not necessarily represent the original syntax used to access this attribute. For example, @myattrib will be stored and returned as float@myattrib.
Parameters
nameThe name of the attribute
typeThe CoreType of the attribute
Returns
A string representing the attribute token.
std::string tokenname ( ) const
inline

Construct and return the full attribute token identifier. See Attribute::tokenFromNameType.

Returns
A string representing the attribute token.
tokens::CoreType type ( ) const
inline

Access the type that was used to access this attribute.

Returns
The type used to access this attribute 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