xpcom/ds/nsWhitespaceTokenizer.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef __nsWhitespaceTokenizer_h
   7 #define __nsWhitespaceTokenizer_h
   8
   9 #include "mozilla/RangedPtr.h"
  10 #include "nsDependentSubstring.h"
  11 #include "nsCRT.h"
  12
  13 template<typename DependentSubstringType, bool IsWhitespace(char16_t)>
  14 class nsTWhitespaceTokenizer
  15 {
  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   {
  27     while (mIter < mEnd && IsWhitespace(*mIter)) {
  28       mWhitespaceBeforeFirstToken = true;
  29       ++mIter;
  30     }
  31   }
  32
  33   /**
  34    * Checks if any more tokens are available.
  35    */
  36   bool hasMoreTokens() const
  37   {
  38     return mIter < mEnd;
  39   }
  40
  41   /*
  42    * Returns true if there is whitespace prior to the first token.
  43    */
  44   bool whitespaceBeforeFirstToken() const
  45   {
  46     return mWhitespaceBeforeFirstToken;
  47   }
  48
  49   /*
  50    * Returns true if there is any whitespace after the current token.
  51    * This is always true unless we're reading the last token.
  52    */
  53   bool whitespaceAfterCurrentToken() const
  54   {
  55     return mWhitespaceAfterCurrentToken;
  56   }
  57
  58   /**
  59    * Returns the next token.
  60    */
  61   const DependentSubstringType nextToken()
  62   {
  63     const mozilla::RangedPtr<const CharType> tokenStart = mIter;
  64     while (mIter < mEnd && !IsWhitespace(*mIter)) {
  65       ++mIter;
  66     }
  67     const mozilla::RangedPtr<const CharType> tokenEnd = mIter;
  68     mWhitespaceAfterCurrentToken = false;
  69     while (mIter < mEnd && IsWhitespace(*mIter)) {
  70       mWhitespaceAfterCurrentToken = true;
  71       ++mIter;
  72     }
  73     return Substring(tokenStart.get(), tokenEnd.get());
  74   }
  75
  76 private:
  77   mozilla::RangedPtr<const CharType> mIter;
  78   const mozilla::RangedPtr<const CharType> mEnd;
  79   bool mWhitespaceBeforeFirstToken;
  80   bool mWhitespaceAfterCurrentToken;
  81 };
  82
  83 template<bool IsWhitespace(char16_t) = NS_IsAsciiWhitespace>
  84 class nsWhitespaceTokenizerTemplate
  85   : public nsTWhitespaceTokenizer<nsDependentSubstring, IsWhitespace>
  86 {
  87 public:
  88   explicit nsWhitespaceTokenizerTemplate(const nsSubstring& aSource)
  89     : nsTWhitespaceTokenizer<nsDependentSubstring, IsWhitespace>(aSource)
  90   {
  91   }
  92 };
  93
  94 typedef nsWhitespaceTokenizerTemplate<> nsWhitespaceTokenizer;
  95
  96 template<bool IsWhitespace(char16_t) = NS_IsAsciiWhitespace>
  97 class nsCWhitespaceTokenizerTemplate
  98   : public nsTWhitespaceTokenizer<nsDependentCSubstring, IsWhitespace>
  99 {
 100 public:
 101   explicit nsCWhitespaceTokenizerTemplate(const nsCSubstring& aSource)
 102     : nsTWhitespaceTokenizer<nsDependentCSubstring, IsWhitespace>(aSource)
 103   {
 104   }
 105 };
 106
 107 typedef nsCWhitespaceTokenizerTemplate<> nsCWhitespaceTokenizer;
 108
 109 #endif /* __nsWhitespaceTokenizer_h */