Packages

  • package root
    Definition Classes
    root
  • package io
    Definition Classes
    root
  • package dylemma
    Definition Classes
    io
  • package spac

    SPaC (short for "Streaming Parser Combinators") is a library for building stream consumers in a declarative style, specialized for tree-like data types like XML and JSON.

    SPaC (short for "Streaming Parser Combinators") is a library for building stream consumers in a declarative style, specialized for tree-like data types like XML and JSON.

    Many utilities for handling XML and JSON data involve parsing the entire "document" to some DOM model, then inspecting and transforming that model to extract information. The downside to these utilities is that when the document is very large, the DOM may not fit in memory. The workaround for this type of problem is to treat the document as a stream of "events", e.g. "StartElement" and "EndElement" for XML, or "StartObject" and "EndObject" for JSON. The downside to this workaround is that writing code to handle these streams can be complicated and error-prone, especially when the DOM is complicated.

    SPaC's goal is to drastically simplify the process of creating code to handle these streams.

    This package contains the "core" SPaC traits; Parser, Transformer, Splitter, and ContextMatcher.

    See the xml and json subpackages (provided by the xml-spac and json-spac libraries respectively) for specific utilities related to handling XML and JSON event streams.

    Definition Classes
    dylemma
  • object Parser

    Definition Classes
    spac
  • FollowedBy
  • Handler
  • InvariantOps
  • ParserFollowedByOps
  • Stateless

trait Handler[-In, +Out] extends AnyRef

An internally-mutable representation of a Parser, which reacts to inputs from a data stream and eventually produces a result.

Source
Parser.scala
Linear Supertypes
AnyRef, Any
Known Subclasses
Stateless, Handler, ParserDelay, ParserDrain, Handler, ParserFind, ParserFirst, ParserFirstOpt, Handler, Handler, ParserHandlerForBuilder, Handler, Handler, Handler, ParserPure, Handler, ParserTap, Handler, TopLevelParserHandler
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Inherited
  1. Handler
  2. AnyRef
  3. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Visibility
  1. Public
  2. Protected

Abstract Value Members

  1. abstract def finish(): Out

    Signal the end of the data stream to this handler, forcing it to generate a result.

    Signal the end of the data stream to this handler, forcing it to generate a result. Handlers may throw exceptions in response to this, such as a handler which wants the first event from an empty stream.

    Further calls to step or finish after the first call to finish will result in undefined behavior. The general assumption is that a handler should be discarded after its finish method is called.

    returns

    the final result of this parser

  2. abstract def step(in: In): Either[Out, Handler[In, Out]]

    Advance the state of this handler by accepting a single input of type In.

    Advance the state of this handler by accepting a single input of type In. If doing so would cause this parser to complete, return a Left containing the output. Otherwise, return a Right containing the next parser state.

    Handlers are assumed to be internally-mutable, so it is acceptable to simply update some internal state and then return Right(this), although in some cases it will be desirable to return a separate handler entirely.

    in

    A single input event from a data stream

    returns

    If the input would finish the parser, return a Left containing the result. Otherwise, return a Right containing a Handler which represents the next parsing state. The handler in a Right may be this handler, or a completely separate one.

Concrete Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toany2stringadd[Handler[In, Out]] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (Handler[In, Out], B)
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toArrowAssoc[Handler[In, Out]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  6. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  7. def asTopLevelHandler(caller: SpacTraceElement): Handler[In, Out]

    Wraps this handler as a "top level" handler, which will inject a SpacTraceElement (representing the current input or the "EOF" signal) to any exception is thrown by this handler when calling its step or finish methods.

    Wraps this handler as a "top level" handler, which will inject a SpacTraceElement (representing the current input or the "EOF" signal) to any exception is thrown by this handler when calling its step or finish methods.

    Used internally by Parser's parse methods.

  8. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native()
  9. def ensuring(cond: (Handler[In, Out]) => Boolean, msg: => Any): Handler[In, Out]
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toEnsuring[Handler[In, Out]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  10. def ensuring(cond: (Handler[In, Out]) => Boolean): Handler[In, Out]
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toEnsuring[Handler[In, Out]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  11. def ensuring(cond: Boolean, msg: => Any): Handler[In, Out]
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toEnsuring[Handler[In, Out]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  12. def ensuring(cond: Boolean): Handler[In, Out]
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toEnsuring[Handler[In, Out]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  13. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  14. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  15. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  16. def formatted(fmtstr: String): String
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toStringFormat[Handler[In, Out]] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  17. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  18. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  19. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  20. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  21. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  22. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  23. def stepMany[C[_], In2 <: In](inputs: C[In2])(implicit C: Unconsable[C]): Either[(Out, C[In2]), Handler[In, Out]]

    Convenience function to call step on a sequence of inputs all at once.

    Convenience function to call step on a sequence of inputs all at once. If the step returns a result, this method will return a Left containing that result and the remainder of the inputs that were not consumed. If the inputs run out before the handler returns a result from a step, this method will return a Right containing the latest state of the handler. This method will not call the handler's finish().

    In general, you won't call this method directly. Instead, use one of the Parser trait's parse methods.

    C

    An Unconsable collection, i.e. List or cats.data.Chain

    In2

    Subtype of In, or In (to satisfy contravariance)

    inputs

    A sequence of inputs

    C

    Evidence that the inputs has a head/tail split operation

    returns

    Either the handler's result paired with the remaining inputs, or the new handler state

  24. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  25. def toString(): String
    Definition Classes
    AnyRef → Any
  26. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  27. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  28. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()

Deprecated Value Members

  1. def →[B](y: B): (Handler[In, Out], B)
    Implicit
    This member is added by an implicit conversion from Handler[In, Out] toArrowAssoc[Handler[In, Out]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @deprecated
    Deprecated

    (Since version 2.13.0) Use -> instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd fromHandler[In, Out] to any2stringadd[Handler[In, Out]]

Inherited by implicit conversion StringFormat fromHandler[In, Out] to StringFormat[Handler[In, Out]]

Inherited by implicit conversion Ensuring fromHandler[In, Out] to Ensuring[Handler[In, Out]]

Inherited by implicit conversion ArrowAssoc fromHandler[In, Out] to ArrowAssoc[Handler[In, Out]]

Ungrouped