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.state contains combinators that interact with the context-sensitive functionality in the form of state.
    • 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
  • object state

    This module contains all the functionality and operations for using and manipulating references.

    This module contains all the functionality and operations for using and manipulating references.

    These often have a role in performing context-sensitive parsing tasks, where a Turing-powerful system is required. While flatMap is capable of such parsing, it is much less efficient than the use of references, though slightly more flexible. In particular, the persist combinator enabled by StateCombinators can serve as a drop-in replacement for flatMap in many scenarios.

    Definition Classes
    parsley
    Since

    4.5.0

  • Ref
  • RefMaker
  • StateCombinators

class Ref[A] extends AnyRef

This class is used to index references within the mutable state.

Source
state.scala
Note

it is undefined behaviour to use a reference in multiple different independent parsers. You should be careful to parameterise the references in shared parsers and allocate fresh ones for each "top-level" parser you will run.

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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. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  5. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native()
  6. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  7. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  8. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  9. def get: Parsley[A]

    This combinator injects the value stored in this reference into a parser.

    This combinator injects the value stored in this reference into a parser.

    Allows for the value stored in this reference to be purely injected into the parsing context. No input is consumed in this process, and it cannot fail.

    returns

    a parser that returns the value stored in this reference.

    Example:

    1. Get-Get Law: 

      r.get *> r.get == r.get
r.get <~> r.get == r.get.map(x => (x, x))
    Since

    3.2.0

  10. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  11. def gets[B](pf: Parsley[(A) => B]): Parsley[B]

    This combinator injects the value stored in this reference into a parser after applying a function obtained from a parser to it.

    This combinator injects the value stored in this reference into a parser after applying a function obtained from a parser to it.

    First, pf is parsed, producing the function f on success. Then, the value stored in this reference x is applied to the function f. The combinator returns f(x). Only pf is allowed to consume input. If pf fails, the combinator fails, otherwise it will succeed.

    B

    the desired result type.

    pf

    the parser that produces the function used to transform the value in this reference.

    returns

    the value stored in this reference applied to a function generated from pf.

    Since

    3.2.0

  12. def gets[B](f: (A) => B): Parsley[B]

    This combinator injects the value stored in this reference into a parser after applying a function to it.

    This combinator injects the value stored in this reference into a parser after applying a function to it.

    Allows for the value stored in this reference to be purely injected into the parsing context but the function f is applied first. No input is consumed in this process, and it cannot fail.

    B

    the desired result type.

    f

    the function used to transform the value in this reference.

    returns

    the value stored in this reference applied to f.

    Since

    3.2.0

  13. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  14. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  15. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  16. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  17. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  18. def rollback[B](p: Parsley[B]): Parsley[B]

    This combinator rolls-back any changes to this reference made by a given parser if it fails.

    This combinator rolls-back any changes to this reference made by a given parser if it fails.

    First get the current value in this reference xold. Then parse p, if it succeeds, producing y, then y is returned and this reference retains its value post-p. Otherwise, if p failed without consuming input, xold is placed back into this reference and this combinator fails.

    This can be used in conjunction with local to make an almost unconditional state restore: 

    // `r`'s state is always rolled back after `p` unless it fails having consumed input.
r.rollback(r.local(x)(p))
    p

    the parser to perform.

    returns

    the result of the parser p, if any.

    Since

    3.2.0

  19. def set(p: Parsley[A]): Parsley[Unit]

    This combinator stores a new value into this reference.

    This combinator stores a new value into this reference.

    First, parse p to obtain its result x. Then store x into this reference without any further effect. If p fails this combinator fails.

    p

    the parser that produces the value to store in the reference.

    Examples:

    1. Get-Set Law: 

      r.set(r.get) == unit
      2. ,

    2. Set-Set Law: 

      // only when `q` does not inspect the value of `r`!
r.set(p) *> r.set(q) == p *> r.set(q)
    Since

    4.5.0

  20. def set(x: A): Parsley[Unit]

    This combinator stores a new value into this reference.

    This combinator stores a new value into this reference.

    Without any other effect, the value x will be placed into this reference.

    x

    the value to place in the reference.

    Examples:

    1. Set-Get Law: 

      r.set(x) *> r.get == r.set(x).as(x)
      2. ,

    2. Set-Set Law: 

      r.set(x) *> r.set(y) == r.set(y)
    Since

    4.5.0

  21. def setDuring[B](p: Parsley[A])(q: => Parsley[B]): Parsley[B]

    This combinator changed the value stored in this reference for the duration of a given parser, resetting it afterwards.

    This combinator changed the value stored in this reference for the duration of a given parser, resetting it afterwards.

    First get the current value in this reference xold, then parse p to get the result x, placing it into this reference without any further effect. Then, parse q, producing result y on success. Finally, put xold back into this reference and return y. If p or q fail, the whole combinator fails and the state is not restored.

    p

    the parser whose return value is placed in this reference.

    q

    the parser to execute with the adjusted state.

    returns

    the parser that performs q with the modified state.

    Since

    4.5.0

  22. def setDuring[B](x: A)(p: Parsley[B]): Parsley[B]

    This combinator changed the value stored in this reference for the duration of a given parser, resetting it afterwards.

    This combinator changed the value stored in this reference for the duration of a given parser, resetting it afterwards.

    First get the current value in this reference xold, then place x into this reference without any further effect. Then, parse p, producing result y on success. Finally, put xold back into this reference and return y. If p fails, the whole combinator fails and the state is not restored.

    x

    the value to place into this reference.

    p

    the parser to execute with the adjusted state.

    returns

    the parser that performs p with the modified state x.

    Example:

    1. Set-Set Law: 

      r.set(x) *> r.setDuring(y)(p) == r.set(y) *> p <* r.set(x)
    Since

    4.5.0

  23. def sets[B](p: Parsley[B], f: (B) => A): Parsley[Unit]

    This combinator stores a new value into this reference.

    This combinator stores a new value into this reference.

    First, parse p to obtain its result x. Then store f(x) into this reference without any further effect. If p fails this combinator fails.

    Equivalent to 

    this.set(p.map(f))
    p

    the parser that produces the value to store in the reference.

    f

    a function which adapts the result of p so that it can fit into this reference.

    Since

    4.5.0

  24. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  25. def toString(): String
    Definition Classes
    AnyRef → Any
  26. def update(pf: Parsley[(A) => A]): Parsley[Unit]

    This combinator modifies the value stored in this reference with a function.

    This combinator modifies the value stored in this reference with a function.

    First, parse pf to obtain its result f. Then get the value stored in this reference, x, and put back f(x). If p fails this combinator fails.

    Equivalent to 

    this.set(this.gets(pf))
    pf

    the parser that produces the function used to transform the value in this reference.

    Since

    4.5.0

  27. def update(f: (A) => A): Parsley[Unit]

    This combinator modifies the value stored in this reference with a function.

    This combinator modifies the value stored in this reference with a function.

    Without any other effect, get the value stored in this reference, x, and put back f(x).

    Equivalent to 

    this.set(this.gets(f))
    f

    the function used to modify this reference's value.

    Since

    4.5.0

  28. def updateDuring[B](f: (A) => A)(p: Parsley[B]): Parsley[B]

    This combinator changed the value stored in this reference for the duration of a given parser, resetting it afterwards.

    This combinator changed the value stored in this reference for the duration of a given parser, resetting it afterwards.

    First get the current value in this reference xold, then place f(xold) into this reference without any further effect. Then, parse p, producing result y on success. Finally, put xold back into this reference and return y. If p fails, the whole combinator fails and the state is not restored.

    f

    the function used to modify the value in this reference.

    p

    the parser to execute with the adjusted state.

    returns

    the parser that performs p with the modified state.

    Example:

    1. Set-Set Law and Set-Get Law: 

      r.set(x) *> r.updateDuring(f)(p) == r.set(f(x)) *> p <* r.set(x)
    Since

    4.5.0

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

Inherited from AnyRef

Inherited from Any

Getters

These combinators allow for the retrieval of the stateful value of a reference, and injecting it into the parsing context. Does not modify the contents of the reference itself.

Setters

These combinators directly update the value contained within a reference. This new value can be provided directly or sourced from a parser.

Modification

These combinators modify the value stored within a reference by using a function. The function used can be provided directly or sourced from a parser.

Local Modification

These combinators allow for some form of local stateful modification. This means that any changes to the reference may be reverted after the execution of the parser: this may be on the parsers success, but it could also involve the parsers failure.

Ungrouped