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Diffstat (limited to 'src/parser-combinators/scala/util/parsing/combinator/lexical/StdLexical.scala')
-rw-r--r-- | src/parser-combinators/scala/util/parsing/combinator/lexical/StdLexical.scala | 87 |
1 files changed, 0 insertions, 87 deletions
diff --git a/src/parser-combinators/scala/util/parsing/combinator/lexical/StdLexical.scala b/src/parser-combinators/scala/util/parsing/combinator/lexical/StdLexical.scala deleted file mode 100644 index 32d7502cda..0000000000 --- a/src/parser-combinators/scala/util/parsing/combinator/lexical/StdLexical.scala +++ /dev/null @@ -1,87 +0,0 @@ -/* __ *\ -** ________ ___ / / ___ Scala API ** -** / __/ __// _ | / / / _ | (c) 2006-2013, LAMP/EPFL ** -** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ ** -** /____/\___/_/ |_/____/_/ | | ** -** |/ ** -\* */ - -package scala -package util.parsing -package combinator -package lexical - -import token._ -import input.CharArrayReader.EofCh -import scala.collection.mutable - -/** This component provides a standard lexical parser for a simple, - * [[http://scala-lang.org Scala]]-like language. It parses keywords and - * identifiers, numeric literals (integers), strings, and delimiters. - * - * To distinguish between identifiers and keywords, it uses a set of - * reserved identifiers: every string contained in `reserved` is returned - * as a keyword token. (Note that `=>` is hard-coded as a keyword.) - * Additionally, the kinds of delimiters can be specified by the - * `delimiters` set. - * - * Usually this component is used to break character-based input into - * bigger tokens, which are then passed to a token-parser (see - * [[scala.util.parsing.combinator.syntactical.TokenParsers]].) - * - * @author Martin Odersky - * @author Iulian Dragos - * @author Adriaan Moors - */ -class StdLexical extends Lexical with StdTokens { - // see `token` in `Scanners` - def token: Parser[Token] = - ( identChar ~ rep( identChar | digit ) ^^ { case first ~ rest => processIdent(first :: rest mkString "") } - | digit ~ rep( digit ) ^^ { case first ~ rest => NumericLit(first :: rest mkString "") } - | '\'' ~ rep( chrExcept('\'', '\n', EofCh) ) ~ '\'' ^^ { case '\'' ~ chars ~ '\'' => StringLit(chars mkString "") } - | '\"' ~ rep( chrExcept('\"', '\n', EofCh) ) ~ '\"' ^^ { case '\"' ~ chars ~ '\"' => StringLit(chars mkString "") } - | EofCh ^^^ EOF - | '\'' ~> failure("unclosed string literal") - | '\"' ~> failure("unclosed string literal") - | delim - | failure("illegal character") - ) - - /** Returns the legal identifier chars, except digits. */ - def identChar = letter | elem('_') - - // see `whitespace in `Scanners` - def whitespace: Parser[Any] = rep[Any]( - whitespaceChar - | '/' ~ '*' ~ comment - | '/' ~ '/' ~ rep( chrExcept(EofCh, '\n') ) - | '/' ~ '*' ~ failure("unclosed comment") - ) - - protected def comment: Parser[Any] = ( - '*' ~ '/' ^^ { case _ => ' ' } - | chrExcept(EofCh) ~ comment - ) - - /** The set of reserved identifiers: these will be returned as `Keyword`s. */ - val reserved = new mutable.HashSet[String] - - /** The set of delimiters (ordering does not matter). */ - val delimiters = new mutable.HashSet[String] - - protected def processIdent(name: String) = - if (reserved contains name) Keyword(name) else Identifier(name) - - private lazy val _delim: Parser[Token] = { - // construct parser for delimiters by |'ing together the parsers for the individual delimiters, - // starting with the longest one -- otherwise a delimiter D will never be matched if there is - // another delimiter that is a prefix of D - def parseDelim(s: String): Parser[Token] = accept(s.toList) ^^ { x => Keyword(s) } - - val d = new Array[String](delimiters.size) - delimiters.copyToArray(d, 0) - scala.util.Sorting.quickSort(d) - (d.toList map parseDelim).foldRight(failure("no matching delimiter"): Parser[Token])((x, y) => y | x) - } - protected def delim: Parser[Token] = _delim -} |