Class SemanticContext.PrecedencePredicate

java.lang.Object
org.graalvm.shadowed.org.antlr.v4.runtime.atn.SemanticContext
org.graalvm.shadowed.org.antlr.v4.runtime.atn.SemanticContext.PrecedencePredicate
All Implemented Interfaces:
Comparable<SemanticContext.PrecedencePredicate>
Enclosing class:
SemanticContext
public static class SemanticContext.PrecedencePredicate extends SemanticContext implements Comparable<SemanticContext.PrecedencePredicate>

  • Field Details

    • precedence

      public final int precedence

  • Constructor Details

    • PrecedencePredicate

      protected PrecedencePredicate()

    • PrecedencePredicate

      public PrecedencePredicate(int precedence)

  • Method Details

    • eval

      public boolean eval(Recognizer<?,?> parser, RuleContext parserCallStack)
      Description copied from class: SemanticContext
      For context independent predicates, we evaluate them without a local context (i.e., null context). That way, we can evaluate them without having to create proper rule-specific context during prediction (as opposed to the parser, which creates them naturally). In a practical sense, this avoids a cast exception from RuleContext to myruleContext.

      For context dependent predicates, we must pass in a local context so that references such as $arg evaluate properly as _localctx.arg. We only capture context dependent predicates in the context in which we begin prediction, so we passed in the outer context here in case of context dependent predicate evaluation.

      Specified by:
      eval in class SemanticContext

    • evalPrecedence

      public SemanticContext evalPrecedence(Recognizer<?,?> parser, RuleContext parserCallStack)
      Description copied from class: SemanticContext
      Evaluate the precedence predicates for the context and reduce the result.
      Overrides:
      evalPrecedence in class SemanticContext
      Parameters:
      parser - The parser instance.
      parserCallStack -
      Returns:
      The simplified semantic context after precedence predicates are evaluated, which will be one of the following values.
      • SemanticContext.Empty.Instance: if the predicate simplifies to true after precedence predicates are evaluated.
      • null: if the predicate simplifies to false after precedence predicates are evaluated.
      • this: if the semantic context is not changed as a result of precedence predicate evaluation.
      • A non-null SemanticContext: the new simplified semantic context after precedence predicates are evaluated.

    • compareTo

      public int compareTo(SemanticContext.PrecedencePredicate o)
      Specified by:
      compareTo in interface Comparable<SemanticContext.PrecedencePredicate>

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object

    • toString

      public String toString()
      Overrides:
      toString in class Object