Interface CstDef

Convenience method, same as MANY but the repetition is of one or more. failing to match at least one repetition will result in a parsing error and cause a parsing error.

Convenience method, same as MANY_SEP but the repetition is of one or more. failing to match at least one repetition will result in a parsing error and cause the parser to attempt error recovery.

Note that an additional optional property ERR_MSG can be used to provide custom error messages.

A Parsing DSL method use to consume a single Token. In EBNF terms this is equivalent to a Terminal.

A Token will be consumed, IFF the next token in the token vector matches tokType. otherwise the parser may attempt to perform error recovery (if enabled).

The index in the method name indicates the unique occurrence of a terminal consumption inside a the top level rule. What this means is that if a terminal appears more than once in a single rule, each appearance must have a different index.

For example:

  this.RULE("qualifiedName", () => {
  this.CONSUME1(Identifier);
    this.MANY(() => {
      this.CONSUME1(Dot);
      // here we use CONSUME2 because the terminal
      // 'Identifier' has already appeared previously in the
      // the rule 'parseQualifiedName'
      this.CONSUME2(Identifier);
    });
  })
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• See more details on the unique suffixes requirement.

Parsing DSL method, that indicates a repetition of zero or more. This is equivalent to EBNF repetition {...}.

Note that there are two syntax forms:

• Passing the grammar action directly:

    this.MANY(() => {
      this.CONSUME(Comma)
      this.CONSUME(Digit)
     })
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• using an "options" object:

    this.MANY({
      GATE: predicateFunc,
      DEF: () => {
             this.CONSUME(Comma)
             this.CONSUME(Digit)
           }
    });
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The optional 'GATE' property in "options" object form can be used to add constraints to invoking the grammar action.

As in CONSUME the index in the method name indicates the occurrence of the repetition production in it's top rule.

Parsing DSL method, that indicates a repetition of zero or more with a separator Token between the repetitions.

Example:

    this.MANY_SEP({
        SEP:Comma,
        DEF: () => {
            this.CONSUME(Number};
            // ...
        })
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Note that because this DSL method always requires more than one argument the options object is always required and it is not possible to use a shorter form like in the MANY DSL method.

Note that for the purposes of deciding on whether or not another iteration exists Only a single Token is examined (The separator). Therefore if the grammar being implemented is so "crazy" to require multiple tokens to identify an item separator please use the more basic DSL methods to implement it.

As in CONSUME the index in the method name indicates the occurrence of the repetition production in it's top rule.

Parsing DSL Method that Indicates an Optional production. in EBNF notation this is equivalent to: "[...]".

Note that there are two syntax forms:

• Passing the grammar action directly:

    this.OPTION(() => {
      this.CONSUME(Digit)}
    );
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• using an "options" object:

    this.OPTION({
      GATE:predicateFunc,
      DEF: () => {
        this.CONSUME(Digit)
    }});
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The optional 'GATE' property in "options" object form can be used to add constraints to invoking the grammar action.

As in CONSUME the index in the method name indicates the occurrence of the optional production in it's top rule.

Parsing DSL method that indicates a choice between a set of alternatives must be made. This is equivalent to an EBNF alternation (A | B | C | D ...), except that the alternatives are ordered like in a PEG grammar. This means that the first matching alternative is always chosen.

There are several forms for the inner alternatives array:

• Passing alternatives array directly:

    this.OR([
      { ALT:() => { this.CONSUME(One) }},
      { ALT:() => { this.CONSUME(Two) }},
      { ALT:() => { this.CONSUME(Three) }}
    ])
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• Passing alternative array directly with predicates (GATE):

    this.OR([
      { GATE: predicateFunc1, ALT:() => { this.CONSUME(One) }},
      { GATE: predicateFuncX, ALT:() => { this.CONSUME(Two) }},
      { GATE: predicateFuncX, ALT:() => { this.CONSUME(Three) }}
    ])
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• These syntax forms can also be mixed:

    this.OR([
      {
        GATE: predicateFunc1,
        ALT:() => { this.CONSUME(One) }
      },
      { ALT:() => { this.CONSUME(Two) }},
      { ALT:() => { this.CONSUME(Three) }}
    ])
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• Additionally an "options" object may be used:

    this.OR({
      DEF:[
        { ALT:() => { this.CONSUME(One) }},
        { ALT:() => { this.CONSUME(Two) }},
        { ALT:() => { this.CONSUME(Three) }}
      ],
      // OPTIONAL property
      ERR_MSG: "A Number"
    })
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The 'predicateFuncX' in the long form can be used to add constraints to choosing the alternative.

As in CONSUME the index in the method name indicates the occurrence of the alternation production in it's top rule.