Special symbols in actions - ANTLR 3

This table describes the complete set of special symbols you can use in actions within your grammar. These are translated by the codegen/action.g ANTLR v3 grammar (in filter mode). The rules mentioned below are found in action.g

Syntax	Description
$enclosingRule.attr	x is enclosing rule, y is a return value, parameter, or predefined property. Rule ENCLOSING_RULE_SCOPE_ATTR. r[int i] returns [int j] : {$r.i, $r.j, $r.start, $r.stop, $r.st, $r.tree} ;
$tokenLabel.prop $tokenRef.prop	token scope attribute. Rule TOKEN_SCOPE_ATTR.
$rulelabel.attr $ruleref.attr	Rule RULE_SCOPE_ATTR.
$label	either a token label or token/rule list label like label+=expr. Rule LABEL_REF.
$tokenref	in a non-lexer grammar ISOLATED_TOKEN_REF
$lexerruleref	Yields a Token object created from that rule or fragment rule. Rule ISOLATED_LEXER_RULE_REF.
$y	return value, parameter, predefined rule property, or token/rule reference within enclosing rule's outermost alt. y must be a "local" reference; i.e., it must be referring to something defined within the enclosing rule. Rule LOCAL_ATTR. r[int i] returns [int j] : {$i, $j, $start, $stop, $st, $tree} ;
$x::y	the only way to access the attributes within a dynamic scope regardless of whether or not you are in the defining rule. Rule DYNAMIC_SCOPE_ATTR. scope Symbols { List names; } r scope {int i;} scope Symbols; : {$r::i=3;} s {$Symbols::names;} ; s : {$r::i; $Symbols::names;} ;
$x[-1]::y	previous (just under top of stack). Rule DYNAMIC_NEGATIVE_INDEXED_SCOPE_ATTR.
$x[-i]::y	top of stack - i where the '-' MUST BE PRESENT; i.e., i cannot simply be negative without the '-' sign! Rule DYNAMIC_NEGATIVE_INDEXED_SCOPE_ATTR.
$x[i]::y	absolute index i (0..size-1). Rule DYNAMIC_NEGATIVE_INDEXED_SCOPE_ATTR.
$x[0]::y	is the absolute 0 indexed element (bottom of the stack). Rule DYNAMIC_NEGATIVE_INDEXED_SCOPE_ATTR.
$x.size()	returns the size of the current stack of the scope. Note: This particular syntax is target-dependent. Look at the target page for other targets than Java.
$r	r is a rule's dynamic scope or a global shared scope. Isolated $rulename is not allowed unless it has a dynamic scope and there is no reference to rulename in the enclosing alternative, which would be ambiguous. Rule ISOLATED_DYNAMIC_SCOPE.

The following symbols relate to StringTemplate templates.

Syntax	Description
%foo(a={},b={},...)	Create instance of template foo, setting attribute arguments. Rule TEMPLATE_INSTANCE.
%({name-expr})(a={},...)	indirect template ctor reference. Rule INDIRECT_TEMPLATE_INSTANCE.
%x.y = z;	set template attribute y of x (always set never get attr) to z [languages like python without ';' must still use the ';' which the code generator is free to remove during code gen]. Rule SET_ATTRIBUTE.
%{expr}.y = z;	template attribute y of StringTemplate-typed expr to z. Rule SET_EXPR_ATTRIBUTE.
%{string-expr}	anonymous template from string expr. Rule TEMPLATE_EXPR.