Packages

  • package root

    This is the documentation for Parsley.

    This is the documentation for Parsley.

    Package structure

    The parsley package contains the Parsley class, as well as the Result, Success, and Failure types. In addition to these, it also contains the following packages and "modules" (a module is defined as being an object which mocks a package):

    • parsley.Parsley contains the bulk of the core "function-style" combinators.
    • parsley.combinator contains many helpful combinators that simplify some common parser patterns.
    • parsley.character contains the combinators needed to read characters and strings, as well as combinators to match specific sub-sets of characters.
    • parsley.debug contains debugging combinators, helpful for identifying faults in parsers.
    • parsley.expr contains the following sub modules:
      • parsley.expr.chain contains combinators used in expression parsing
      • parsley.expr.precedence is a builder for expression parsers built on a precedence table.
      • parsley.expr.infix contains combinators used in expression parsing, but with more permissive types than their equivalents in chain.
      • parsley.expr.mixed contains combinators that can be used for expression parsing, but where different fixities may be mixed on the same level: this is rare in practice.
    • parsley.syntax contains several implicits to add syntactic sugar to the combinators. These are sub-categorised into the following sub modules:
      • parsley.syntax.character contains implicits to allow you to use character and string literals as parsers.
      • parsley.syntax.lift enables postfix application of the lift combinator onto a function (or value).
      • parsley.syntax.zipped enables boths a reversed form of lift where the function appears on the right and is applied on a tuple (useful when type inference has failed) as well as a .zipped method for building tuples out of several combinators.
      • parsley.syntax.extension contains syntactic sugar combinators exposed as implicit classes.
    • parsley.errors contains modules to deal with error messages, their refinement and generation.
    • parsley.lift contains functions which lift functions that work on regular types to those which now combine the results of parsers returning those same types. these are ubiquitous.
    • parsley.ap contains functions which allow for the application of a parser returning a function to several parsers returning each of the argument types.
    • parsley.registers contains combinators that interact with the context-sensitive functionality in the form of registers.
    • parsley.token contains the Lexer class that provides a host of helpful lexing combinators when provided with the description of a language.
    • parsley.position contains parsers for extracting position information.
    • parsley.generic contains some basic implementations of the Parser Bridge pattern (see Design Patterns for Parser Combinators in Scala, or the parsley wiki): these can be used before more specialised generic bridge traits can be constructed.
    Definition Classes
    root
  • package parsley
    Definition Classes
    root
  • package errors

    This package contains various functionality relating to the generation and formatting of error messages.

    This package contains various functionality relating to the generation and formatting of error messages.

    In particular, it includes a collection of combinators for improving error messages within the parser, including labelling and providing additional information. It also contains combinators that can be used to valid data produced by a parser, to ensure it conforms to expected invariances, producing good quality error messages if this is not the case. Finally, this package contains ways of changing the formatting of error messages: this can either be changing how the default String-based errors are formatted, or by injectiing Parsley's errors into a custom error object.

    Definition Classes
    parsley
  • package tokenextractors

    This package contains implementations of token extractors that can be mixed into ErrorBuilder to decide how to extract unexpected tokens from the residual input left over from a parse error.

    This package contains implementations of token extractors that can be mixed into ErrorBuilder to decide how to extract unexpected tokens from the residual input left over from a parse error.

    These are common strategies, and something here is likely to be what is needed. They are all careful to handle unprintable characters and whitespace in a sensible way, and account for unicode codepoints that are wider than a single 16-bit character.

    Definition Classes
    errors
    Since

    4.0.0

  • DefaultErrorBuilder
  • ErrorBuilder
  • ErrorGen
  • SpecialisedGen
  • Token
  • TokenSpan
  • VanillaGen
  • combinator
  • patterns

class VanillaGen[-A] extends ErrorGen[A]

An error generator for Vanilla errors, which can tune the unexpected message and a generated reason.

Source
ErrorGen.scala
Since

4.4.0

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Inherited
  1. VanillaGen
  2. ErrorGen
  3. AnyRef
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  2. Protected

Instance Constructors

  1. new VanillaGen()

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. def adjustWidth(x: A, width: Int): Int

    This method can be overridden to control how wide an error is based on the value and width that produces it.

    This method can be overridden to control how wide an error is based on the value and width that produces it.

    The width provides to this error generator likely comes directly from the span of the parser used to produce the required result. However, this may not be entirely accurate for how the user might want the error to be sized (perhaps there was whitespace, or the parser consumed more input than was necessary to pin-point the problem). In these cases, this method allows for custom logic to derive the actual width of the error message. By default, just returns the given width.

    Definition Classes
    ErrorGen
    Since

    4.4.0

  5. final def apply(p: Parsley[(A, Int)]): Parsley[Nothing]

    This combinator takes a given parser and raises an error based on its returned results.

    This combinator takes a given parser and raises an error based on its returned results.

    The given parser produces a value and a width, which are used to synthesise and raise an error message derived from the value with the given width. This is a safe way of using parser, since it ensures that the result of the given parser p is not optimised out. errGen(p) is similar to withWidth(p).flatMap { case (x, w) => failCombinator(...) }, in that it generates errors in a context-sensitive way. However, this is much more efficient than using the expensive flatMap, so it is provided as a primitive operation.

    Definition Classes
    ErrorGen
    Since

    4.4.0

  6. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  7. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native()
  8. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  9. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  10. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  11. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  12. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  13. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  14. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  15. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  16. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  17. final def parser: Parsley[((A, Int)) => Nothing]

    This parser can be applied (postfix) to a parser returning a value and a width to generate an error message tailored to them.

    This parser can be applied (postfix) to a parser returning a value and a width to generate an error message tailored to them.

    This is not a generally safe operation to be performing, and should only be used within a combinator that is guaranteed to use its results. The optimiser is not aware that the results of the parser this will be applied to will actually be needed, and so may optimise them out. Using this parser inside an arm of select or branch, say, would be safe, because these combinators force the result of their condition to be generated, but p <**> this.parser is not generally safe without a use of impure to guard it. This is what apply accomplishes more safely.

    Definition Classes
    ErrorGen
    Since

    4.4.0

  18. def reason(x: A): Option[String]

    What should the reason component of the error message be (if any) based on the result the offending parser produced?

    What should the reason component of the error message be (if any) based on the result the offending parser produced?

    Since

    4.4.0

  19. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  20. def toString(): String
    Definition Classes
    AnyRef → Any
  21. def unexpected(x: A): UnexpectedItem

    What should the unexpected component of the error message be based on the result the offending parser produced?

    What should the unexpected component of the error message be based on the result the offending parser produced?

    Since

    4.4.0

  22. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  23. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  24. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()

Inherited from ErrorGen[A]

Inherited from AnyRef

Inherited from Any

Ungrouped