xpcom/ds/nsWhitespaceTokenizer.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef __nsWhitespaceTokenizer_h
   8 #define __nsWhitespaceTokenizer_h
   9
  10 #include "mozilla/RangedPtr.h"
  11 #include "nsDependentSubstring.h"
  12 #include "nsCRTGlue.h"
  13
  14 template <typename DependentSubstringType, bool IsWhitespace(char16_t)>
  15 class nsTWhitespaceTokenizer {
  16   typedef typename DependentSubstringType::char_type CharType;
  17   typedef typename DependentSubstringType::substring_type SubstringType;
  18
  19  public:
  20   explicit nsTWhitespaceTokenizer(const SubstringType& aSource)
  21       : mIter(aSource.Data(), aSource.Length()),
  22         mEnd(aSource.Data() + aSource.Length(), aSource.Data(),
  23              aSource.Length()),
  24         mWhitespaceBeforeFirstToken(false),
  25         mWhitespaceAfterCurrentToken(false) {
  26     while (mIter < mEnd && IsWhitespace(*mIter)) {
  27       mWhitespaceBeforeFirstToken = true;
  28       ++mIter;
  29     }
  30   }
  31
  32   /**
  33    * Checks if any more tokens are available.
  34    */
  35   bool hasMoreTokens() const { return mIter < mEnd; }
  36
  37   /*
  38    * Returns true if there is whitespace prior to the first token.
  39    */
  40   bool whitespaceBeforeFirstToken() const {
  41     return mWhitespaceBeforeFirstToken;
  42   }
  43
  44   /*
  45    * Returns true if there is any whitespace after the current token.
  46    * This is always true unless we're reading the last token.
  47    */
  48   bool whitespaceAfterCurrentToken() const {
  49     return mWhitespaceAfterCurrentToken;
  50   }
  51
  52   /**
  53    * Returns the next token.
  54    */
  55   const DependentSubstringType nextToken() {
  56     const mozilla::RangedPtr<const CharType> tokenStart = mIter;
  57     while (mIter < mEnd && !IsWhitespace(*mIter)) {
  58       ++mIter;
  59     }
  60     const mozilla::RangedPtr<const CharType> tokenEnd = mIter;
  61     mWhitespaceAfterCurrentToken = false;
  62     while (mIter < mEnd && IsWhitespace(*mIter)) {
  63       mWhitespaceAfterCurrentToken = true;
  64       ++mIter;
  65     }
  66     return Substring(tokenStart.get(), tokenEnd.get());
  67   }
  68
  69  private:
  70   mozilla::RangedPtr<const CharType> mIter;
  71   const mozilla::RangedPtr<const CharType> mEnd;
  72   bool mWhitespaceBeforeFirstToken;
  73   bool mWhitespaceAfterCurrentToken;
  74 };
  75
  76 template <bool IsWhitespace(char16_t) = NS_IsAsciiWhitespace>
  77 class nsWhitespaceTokenizerTemplate
  78     : public nsTWhitespaceTokenizer<nsDependentSubstring, IsWhitespace> {
  79  public:
  80   explicit nsWhitespaceTokenizerTemplate(const nsAString& aSource)
  81       : nsTWhitespaceTokenizer<nsDependentSubstring, IsWhitespace>(aSource) {}
  82 };
  83
  84 typedef nsWhitespaceTokenizerTemplate<> nsWhitespaceTokenizer;
  85
  86 template <bool IsWhitespace(char16_t) = NS_IsAsciiWhitespace>
  87 class nsCWhitespaceTokenizerTemplate
  88     : public nsTWhitespaceTokenizer<nsDependentCSubstring, IsWhitespace> {
  89  public:
  90   explicit nsCWhitespaceTokenizerTemplate(const nsACString& aSource)
  91       : nsTWhitespaceTokenizer<nsDependentCSubstring, IsWhitespace>(aSource) {}
  92 };
  93
  94 typedef nsCWhitespaceTokenizerTemplate<> nsCWhitespaceTokenizer;
  95
  96 #endif /* __nsWhitespaceTokenizer_h */