antlr-ng
Version:
Next generation ANTLR Tool
40 lines (39 loc) • 1.82 kB
TypeScript
import type { IAttribute } from "./IAttribute.js";
import { ActionAST } from "./ast/ActionAST.js";
/**
* Grammars, rules, and alternatives all have symbols visible to actions. To evaluate attr exprs, ask action for its
* resolver then ask resolver to look up various symbols. Depending on the context, some symbols are available at
* some aren't.
*
* Alternative level:
*
* $x Attribute: rule arguments, return values, predefined rule prop.
* AttributeDict: references to tokens and token labels in the
* current alt (including any elements within subrules contained
* in that outermost alt). x can be rule with scope or a global scope.
* List label: x is a token/rule list label.
* $x.y Attribute: x is surrounding rule, rule/token/label ref
* $s::y Attribute: s is any rule with scope or global scope; y is prop within
*
* Rule level:
*
* $x Attribute: rule arguments, return values, predefined rule prop.
* AttributeDict: references to token labels in *any* alt. x can
* be any rule with scope or global scope.
* List label: x is a token/rule list label.
* $x.y Attribute: x is surrounding rule, label ref (in any alts)
* $s::y Attribute: s is any rule with scope or global scope; y is prop within
*
* Grammar level:
*
* $s AttributeDict: s is a global scope
* $s::y Attribute: s is a global scope; y is prop within
*/
export interface IAttributeResolver {
resolvesToListLabel(x: string, node: ActionAST): boolean;
resolvesToLabel(x: string, node: ActionAST): boolean;
resolvesToAttributeDict(x: string, node: ActionAST): boolean;
resolvesToToken(x: string, node: ActionAST): boolean;
resolveToAttribute(x: string, node: ActionAST): IAttribute | null;
resolveToAttribute(x: string, y: string, node: ActionAST): IAttribute | null;
}