scala.util.parsing.combinator.lexical.Lexical.scala Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of scala-library Show documentation
Show all versions of scala-library Show documentation
Standard library for the Scala Programming Language
/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2006-2013, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.util.parsing
package combinator
package lexical
import token._
import input.CharArrayReader.EofCh
/** This component complements the `Scanners` component with
* common operations for lexical parsers.
*
* Refer to [[scala.util.parsing.combinator.lexical.StdLexical]]
* for a concrete implementation for a simple, Scala-like language.
*
* @author Martin Odersky, Adriaan Moors
*/
abstract class Lexical extends Scanners with Tokens {
/** A character-parser that matches a letter (and returns it).*/
def letter = elem("letter", _.isLetter)
/** A character-parser that matches a digit (and returns it).*/
def digit = elem("digit", _.isDigit)
/** A character-parser that matches any character except the ones given in `cs` (and returns it).*/
def chrExcept(cs: Char*) = elem("", ch => (cs forall (ch != _)))
/** A character-parser that matches a white-space character (and returns it).*/
def whitespaceChar = elem("space char", ch => ch <= ' ' && ch != EofCh)
}