scala.util.parsing.combinator.Parsers

OnceParser

trait OnceParser[+T] extends Parser[T]

A parser whose ~ combinator disallows back-tracking.

Source
Parsers.scala
Linear Supertypes
Parser[T], (Input) ⇒ ParseResult[T], AnyRef, Any
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  1. OnceParser
  2. Parser
  3. Function1
  4. AnyRef
  5. Any
Implicitly
  1. by StringAdd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Abstract Value Members

  1. abstract def apply(in: Input): ParseResult[T]

    An unspecified method that defines the behaviour of this parser.

    An unspecified method that defines the behaviour of this parser.

    returns

    the result of function application.

    Definition Classes
    ParserFunction1

Concrete Value Members

  1. final def !=(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  2. final def !=(arg0: Any): Boolean

    Definition Classes
    Any
  3. final def ##(): Int

    Definition Classes
    AnyRef → Any
  4. def *[U >: T](sep: ⇒ Parser[(U, U) ⇒ U]): Parser[U]

    Returns a parser that repeatedly parses what this parser parses, interleaved with the sep parser.

    Returns a parser that repeatedly parses what this parser parses, interleaved with the sep parser. The sep parser specifies how the results parsed by this parser should be combined.

    returns

    chainl1(this, sep)

    Definition Classes
    Parser
  5. def *: Parser[List[T]]

    Returns a parser that repeatedly parses what this parser parses.

    Returns a parser that repeatedly parses what this parser parses.

    returns

    rep(this)

    Definition Classes
    Parser
  6. def +: Parser[List[T]]

    Returns a parser that repeatedly (at least once) parses what this parser parses.

    Returns a parser that repeatedly (at least once) parses what this parser parses.

    returns

    rep1(this)

    Definition Classes
    Parser
  7. def ->[B](y: B): (OnceParser[T], B)

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to ArrowAssoc[OnceParser[T]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  8. def <~[U](q: ⇒ Parser[U]): Parser[T]

    A parser combinator for sequential composition which keeps only the left result.

    A parser combinator for sequential composition which keeps only the left result.

    p <~ q succeeds if p succeeds and q succeeds on the input left over by p.

    q

    a parser that will be executed after p (this parser) succeeds -- evaluated at most once, and only when necessary

    returns

    a Parser that -- on success -- returns the result of p.

    Definition Classes
    Parser
    Annotations
    @migration
    Migration

    (Changed in version 2.9.0) The call-by-name argument is evaluated at most once per constructed Parser object, instead of on every need that arises during parsing.

    Note

    <~ has lower operator precedence than ~ or ~>.

  9. final def ==(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  10. final def ==(arg0: Any): Boolean

    Definition Classes
    Any
  11. def >>[U](fq: (T) ⇒ Parser[U]): Parser[U]

    Returns into(fq).

    Returns into(fq).

    Definition Classes
    Parser
  12. def ?: Parser[Option[T]]

    Returns a parser that optionally parses what this parser parses.

    Returns a parser that optionally parses what this parser parses.

    returns

    opt(this)

    Definition Classes
    Parser
  13. def ^?[U](f: PartialFunction[T, U]): Parser[U]

    A parser combinator for partial function application.

    A parser combinator for partial function application.

    p ^? f succeeds if p succeeds AND f is defined at the result of p; in that case, it returns f applied to the result of p.

    f

    a partial function that will be applied to this parser's result (see mapPartial in ParseResult).

    returns

    a parser that succeeds if the current parser succeeds and f is applicable to the result. If so, the result will be transformed by f.

    Definition Classes
    Parser
  14. def ^?[U](f: PartialFunction[T, U], error: (T) ⇒ String): Parser[U]

    A parser combinator for partial function application.

    A parser combinator for partial function application.

    p ^? (f, error) succeeds if p succeeds AND f is defined at the result of p; in that case, it returns f applied to the result of p. If f is not applicable, error(the result of p) should explain why.

    f

    a partial function that will be applied to this parser's result (see mapPartial in ParseResult).

    error

    a function that takes the same argument as f and produces an error message to explain why f wasn't applicable

    returns

    a parser that succeeds if the current parser succeeds and f is applicable to the result. If so, the result will be transformed by f.

    Definition Classes
    Parser
  15. def ^^[U](f: (T) ⇒ U): Parser[U]

    A parser combinator for function application.

    A parser combinator for function application.

    p ^^ f succeeds if p succeeds; it returns f applied to the result of p.

    f

    a function that will be applied to this parser's result (see map in ParseResult).

    returns

    a parser that has the same behaviour as the current parser, but whose result is transformed by f.

    Definition Classes
    Parser
  16. def ^^^[U](v: ⇒ U): Parser[U]

    A parser combinator that changes a successful result into the specified value.

    A parser combinator that changes a successful result into the specified value.

    p ^^^ v succeeds if p succeeds; discards its result, and returns v instead.

    v

    The new result for the parser, evaluated at most once (if p succeeds), not evaluated at all if p fails.

    returns

    a parser that has the same behaviour as the current parser, but whose successful result is v

    Definition Classes
    Parser
    Annotations
    @migration
    Migration

    (Changed in version 2.9.0) The call-by-name argument is evaluated at most once per constructed Parser object, instead of on every need that arises during parsing.

  17. def andThen[A](g: (ParseResult[T]) ⇒ A): (Input) ⇒ A

    Composes two instances of Function1 in a new Function1, with this function applied first.

    Composes two instances of Function1 in a new Function1, with this function applied first.

    A

    the result type of function g

    g

    a function R => A

    returns

    a new function f such that f(x) == g(apply(x))

    Definition Classes
    Function1
    Annotations
    @unspecialized()
  18. def append[U >: T](p0: ⇒ Parser[U]): Parser[U]

    Definition Classes
    Parser
    Annotations
    @migration
    Migration

    (Changed in version 2.9.0) The call-by-name argument is evaluated at most once per constructed Parser object, instead of on every need that arises during parsing.

  19. final def asInstanceOf[T0]: T0

    Definition Classes
    Any
  20. def clone(): AnyRef

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws()
  21. def compose[A](g: (A) ⇒ Input): (A) ⇒ ParseResult[T]

    Composes two instances of Function1 in a new Function1, with this function applied last.

    Composes two instances of Function1 in a new Function1, with this function applied last.

    A

    the type to which function g can be applied

    g

    a function A => T1

    returns

    a new function f such that f(x) == apply(g(x))

    Definition Classes
    Function1
    Annotations
    @unspecialized()
  22. def ensuring(cond: (OnceParser[T]) ⇒ Boolean, msg: ⇒ Any): OnceParser[T]

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to Ensuring[OnceParser[T]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  23. def ensuring(cond: (OnceParser[T]) ⇒ Boolean): OnceParser[T]

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to Ensuring[OnceParser[T]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  24. def ensuring(cond: Boolean, msg: ⇒ Any): OnceParser[T]

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to Ensuring[OnceParser[T]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  25. def ensuring(cond: Boolean): OnceParser[T]

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to Ensuring[OnceParser[T]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  26. final def eq(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  27. def equals(arg0: Any): Boolean

    Definition Classes
    AnyRef → Any
  28. def filter(p: (T) ⇒ Boolean): Parser[T]

    Definition Classes
    Parser
  29. def finalize(): Unit

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws()
  30. def flatMap[U](f: (T) ⇒ Parser[U]): Parser[U]

    Definition Classes
    Parser
  31. def formatted(fmtstr: String): String

    Returns string formatted according to given format string.

    Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to StringFormat[OnceParser[T]] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  32. final def getClass(): Class[_]

    Definition Classes
    AnyRef → Any
  33. def hashCode(): Int

    Definition Classes
    AnyRef → Any
  34. def into[U](fq: (T) ⇒ Parser[U]): Parser[U]

    A parser combinator that parameterizes a subsequent parser with the result of this one.

    A parser combinator that parameterizes a subsequent parser with the result of this one.

    Use this combinator when a parser depends on the result of a previous parser. p should be a function that takes the result from the first parser and returns the second parser.

    p into fq (with fq typically {x => q}) first applies p, and then, if p successfully returned result r, applies fq(r) to the rest of the input.

    From: G. Hutton. Higher-order functions for parsing. J. Funct. Program., 2(3):323--343, 1992.

    fq

    a function that, given the result from this parser, returns the second parser to be applied

    returns

    a parser that succeeds if this parser succeeds (with result x) and if then fq(x) succeeds

    Definition Classes
    Parser
    Example:
    1. def perlRE = "m" ~> (".".r into (separator => """[^%s]*""".format(separator).r <~ separator))
  35. final def isInstanceOf[T0]: Boolean

    Definition Classes
    Any
  36. def map[U](f: (T) ⇒ U): Parser[U]

    Definition Classes
    Parser
  37. def named(n: String): OnceParser.this.type

    Definition Classes
    Parser
  38. final def ne(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  39. final def notify(): Unit

    Definition Classes
    AnyRef
  40. final def notifyAll(): Unit

    Definition Classes
    AnyRef
  41. final def synchronized[T0](arg0: ⇒ T0): T0

    Definition Classes
    AnyRef
  42. def toString(): String

    Definition Classes
    ParserFunction1 → AnyRef → Any
  43. final def wait(): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws()
  44. final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws()
  45. final def wait(arg0: Long): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws()
  46. def withErrorMessage(msg: String): Parser[T]

    Changes the error message produced by a parser.

    Changes the error message produced by a parser.

    This doesn't change the behavior of a parser on neither success nor failure, just on error. The semantics are slightly different than those obtained by doing | error(msg), in that the message produced by this method will always replace the message produced, which is not guaranteed by that idiom.

    For example, parser p below will always produce the designated error message, while q will not produce it if sign is parsed but number is not.

    def p = sign.? ~ number withErrorMessage  "Number expected!"
    def q = sign.? ~ number | error("Number expected!")
    msg

    The message that will replace the default error message.

    returns

    A parser with the same properties and different error message.

    Definition Classes
    Parser
  47. def withFailureMessage(msg: String): Parser[T]

    Changes the failure message produced by a parser.

    Changes the failure message produced by a parser.

    This doesn't change the behavior of a parser on neither success nor error, just on failure. The semantics are slightly different than those obtained by doing | failure(msg), in that the message produced by this method will always replace the message produced, which is not guaranteed by that idiom.

    For example, parser p below will always produce the designated failure message, while q will not produce it if sign is parsed but number is not.

    def p = sign.? ~ number withFailureMessage  "Number expected!"
    def q = sign.? ~ number | failure("Number expected!")
    msg

    The message that will replace the default failure message.

    returns

    A parser with the same properties and different failure message.

    Definition Classes
    Parser
  48. def withFilter(p: (T) ⇒ Boolean): Parser[T]

    Definition Classes
    Parser
  49. def |[U >: T](q: ⇒ Parser[U]): Parser[U]

    A parser combinator for alternative composition.

    A parser combinator for alternative composition.

    p | q succeeds if p succeeds or q succeeds. Note that q is only tried if ps failure is non-fatal (i.e., back-tracking is allowed).

    q

    a parser that will be executed if p (this parser) fails (and allows back-tracking)

    returns

    a Parser that returns the result of the first parser to succeed (out of p and q) The resulting parser succeeds if (and only if)

    • p succeeds, or
    • if p fails allowing back-tracking and q succeeds.
    Definition Classes
    Parser
  50. def |||[U >: T](q0: ⇒ Parser[U]): Parser[U]

    A parser combinator for alternative with longest match composition.

    A parser combinator for alternative with longest match composition.

    p ||| q succeeds if p succeeds or q succeeds. If p and q both succeed, the parser that consumed the most characters accepts.

    q0

    a parser that accepts if p consumes less characters. -- evaluated at most once, and only when necessary

    returns

    a Parser that returns the result of the parser consuming the most characters (out of p and q).

    Definition Classes
    Parser
    Annotations
    @migration
    Migration

    (Changed in version 2.9.0) The call-by-name argument is evaluated at most once per constructed Parser object, instead of on every need that arises during parsing.

  51. def ~[U](p: ⇒ Parser[U]): Parser[~[T, U]]

    A parser combinator for sequential composition.

    A parser combinator for sequential composition.

    p ~ q succeeds if p succeeds and q succeeds on the input left over by p.

    returns

    a Parser that -- on success -- returns a ~ (like a Pair, but easier to pattern match on) that contains the result of p and that of q. The resulting parser fails if either p or q fails.

    Definition Classes
    OnceParserParser
  52. def ~![U](p: ⇒ Parser[U]): Parser[~[T, U]]

    A parser combinator for non-back-tracking sequential composition.

    A parser combinator for non-back-tracking sequential composition.

    p ~! q succeeds if p succeeds and q succeeds on the input left over by p. In case of failure, no back-tracking is performed (in an earlier parser produced by the | combinator).

    p

    a parser that will be executed after p (this parser) succeeds

    returns

    a Parser that -- on success -- returns a ~ (like a Pair, but easier to pattern match on) that contains the result of p and that of q. The resulting parser fails if either p or q fails, this failure is fatal.

    Definition Classes
    Parser
  53. def ~>[U](q: ⇒ Parser[U]): Parser[U]

    A parser combinator for sequential composition which keeps only the right result.

    A parser combinator for sequential composition which keeps only the right result.

    p ~> q succeeds if p succeeds and q succeeds on the input left over by p.

    q

    a parser that will be executed after p (this parser) succeeds -- evaluated at most once, and only when necessary.

    returns

    a Parser that -- on success -- returns the result of q.

    Definition Classes
    Parser
    Annotations
    @migration
    Migration

    (Changed in version 2.9.0) The call-by-name argument is evaluated at most once per constructed Parser object, instead of on every need that arises during parsing.

  54. def [B](y: B): (OnceParser[T], B)

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to ArrowAssoc[OnceParser[T]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Shadowed Implicit Value Members

  1. def +(other: String): String

    Implicit information
    This member is added by an implicit conversion from OnceParser[T] to StringAdd[OnceParser[T]] performed by method StringAdd in scala.Predef.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (onceParser: StringAdd[OnceParser[T]]).+(other)
    Definition Classes
    StringAdd

Inherited from Parser[T]

Inherited from (Input) ⇒ ParseResult[T]

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion StringAdd from OnceParser[T] to StringAdd[OnceParser[T]]

Inherited by implicit conversion StringFormat from OnceParser[T] to StringFormat[OnceParser[T]]

Inherited by implicit conversion Ensuring from OnceParser[T] to Ensuring[OnceParser[T]]

Inherited by implicit conversion ArrowAssoc from OnceParser[T] to ArrowAssoc[OnceParser[T]]

Ungrouped