scala.util.parsing.combinator.Parsers

Parser

abstract class Parser[+T] extends (Input) ⇒ ParseResult[T]

The root class of parsers. Parsers are functions from the Input type to ParseResult.

Source
Parsers.scala
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  1. Parser
  2. Function1
  3. AnyRef
  4. Any
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  1. by any2stringadd
  2. by any2stringfmt
  3. by any2ArrowAssoc
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Instance Constructors

  1. new Parser()

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

    Test two objects for inequality.

    Test two objects for inequality.

    returns

    true if !(this == that), false otherwise.

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

    Equivalent to x.hashCode except for boxed numeric types and null.

    Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

    returns

    a hash value consistent with ==

    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)

  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)

  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)

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

    Implicit information
    This member is added by an implicit conversion from Parser[T] to ArrowAssoc[Parser[T]] performed by method any2ArrowAssoc 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.

    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

    Test two objects for equality.

    Test two objects for equality. The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

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

    Returns into(fq).

  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)

  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.

  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.

  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.

  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

    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]

    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

    Cast the receiver object to be of type T0.

    Cast the receiver object to be of type T0.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

    returns

    the receiver object.

    Definition Classes
    Any
    Exceptions thrown
    ClassCastException

    if the receiver object is not an instance of the erasure of type T0.

  20. def clone(): AnyRef

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the clone method is platform dependent.

    returns

    a copy of the receiver object.

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws()
    Note

    not specified by SLS as a member of AnyRef

  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: (Parser[T]) ⇒ Boolean, msg: ⇒ Any): Parser[T]

    Implicit information
    This member is added by an implicit conversion from Parser[T] to Ensuring[Parser[T]] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  23. def ensuring(cond: (Parser[T]) ⇒ Boolean): Parser[T]

    Implicit information
    This member is added by an implicit conversion from Parser[T] to Ensuring[Parser[T]] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  24. def ensuring(cond: Boolean, msg: ⇒ Any): Parser[T]

    Implicit information
    This member is added by an implicit conversion from Parser[T] to Ensuring[Parser[T]] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  25. def ensuring(cond: Boolean): Parser[T]

    Implicit information
    This member is added by an implicit conversion from Parser[T] to Ensuring[Parser[T]] performed by method any2Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  26. final def eq(arg0: AnyRef): Boolean

    Tests whether the argument (arg0) is a reference to the receiver object (this).

    Tests whether the argument (arg0) is a reference to the receiver object (this).

    The eq method implements an equivalence relation on non-null instances of AnyRef, and has three additional properties:

    • It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false.
    • For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false.
    • null.eq(null) returns true.

    When overriding the equals or hashCode methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).

    returns

    true if the argument is a reference to the receiver object; false otherwise.

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

    The equality method for reference types.

    The equality method for reference types. Default implementation delegates to eq.

    See also equals in scala.Any.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

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

  29. def finalize(): Unit

    Called by the garbage collector on the receiver object when there are no more references to the object.

    Called by the garbage collector on the receiver object when there are no more references to the object.

    The details of when and if the finalize method is invoked, as well as the interaction between finalize and non-local returns and exceptions, are all platform dependent.

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws()
    Note

    not specified by SLS as a member of AnyRef

  30. def flatMap[U](f: (T) ⇒ Parser[U]): Parser[U]

  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 Parser[T] to StringFormat performed by method any2stringfmt in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  32. final def getClass(): Class[_]

    A representation that corresponds to the dynamic class of the receiver object.

    A representation that corresponds to the dynamic class of the receiver object.

    The nature of the representation is platform dependent.

    returns

    a representation that corresponds to the dynamic class of the receiver object.

    Definition Classes
    AnyRef → Any
    Note

    not specified by SLS as a member of AnyRef

  33. def hashCode(): Int

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in scala.Any.

    returns

    the hash code value for this object.

    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

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

    Test whether the dynamic type of the receiver object is T0.

    Test whether the dynamic type of the receiver object is T0.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

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

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

  38. final def ne(arg0: AnyRef): Boolean

    Equivalent to !(this eq that).

    Equivalent to !(this eq that).

    returns

    true if the argument is not a reference to the receiver object; false otherwise.

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

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Definition Classes
    AnyRef
    Note

    not specified by SLS as a member of AnyRef

  40. final def notifyAll(): Unit

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    Definition Classes
    AnyRef
    Note

    not specified by SLS as a member of AnyRef

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

    Definition Classes
    AnyRef
  42. def toString(): String

    Creates a String representation of this object.

    Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.

    returns

    a String representation of the object.

    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.

  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.

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

  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.
  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).

    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](q: ⇒ 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.

    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 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.

    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.

  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.

  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.

    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): (Parser[T], B)

    Implicit information
    This member is added by an implicit conversion from Parser[T] to ArrowAssoc[Parser[T]] performed by method any2ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Shadowed Implict Value Members

  1. def +(other: String): String

    Implicit information
    This member is added by an implicit conversion from Parser[T] to StringAdd performed by method any2stringadd 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:
    (parser: StringAdd).+(other)
    Definition Classes
    StringAdd
  2. val self: Any

    Implicit information
    This member is added by an implicit conversion from Parser[T] to StringAdd performed by method any2stringadd in scala.Predef.
    Shadowing
    This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
    To access this member you can use a type ascription:
    (parser: StringAdd).self
    Definition Classes
    StringAdd
  3. val self: Any

    Implicit information
    This member is added by an implicit conversion from Parser[T] to StringFormat performed by method any2stringfmt in scala.Predef.
    Shadowing
    This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
    To access this member you can use a type ascription:
    (parser: StringFormat).self
    Definition Classes
    StringFormat

Deprecated Value Members

  1. def x: Parser[T]

    Implicit information
    This member is added by an implicit conversion from Parser[T] to ArrowAssoc[Parser[T]] performed by method any2ArrowAssoc in scala.Predef.
    Shadowing
    This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
    To access this member you can use a type ascription:
    (parser: ArrowAssoc[Parser[T]]).x
    Definition Classes
    ArrowAssoc
    Annotations
    @deprecated
    Deprecated

    (Since version 2.10.0) Use leftOfArrow instead

  2. def x: Parser[T]

    Implicit information
    This member is added by an implicit conversion from Parser[T] to Ensuring[Parser[T]] performed by method any2Ensuring in scala.Predef.
    Shadowing
    This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
    To access this member you can use a type ascription:
    (parser: Ensuring[Parser[T]]).x
    Definition Classes
    Ensuring
    Annotations
    @deprecated
    Deprecated

    (Since version 2.10.0) Use resultOfEnsuring instead

Inherited from (Input) ⇒ ParseResult[T]

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from Parser[T] to StringAdd

Inherited by implicit conversion any2stringfmt from Parser[T] to StringFormat

Inherited by implicit conversion any2ArrowAssoc from Parser[T] to ArrowAssoc[Parser[T]]

Inherited by implicit conversion any2Ensuring from Parser[T] to Ensuring[Parser[T]]

Ungrouped