/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsStringIterator_h___

#define nsStringIterator_h___

#include "nsCharTraits.h"

#include "nsAlgorithm.h"

#include "nsDebug.h"

/**

 * @see nsTAString

 */

template <class CharT>

class nsReadingIterator

{

public:

  typedef nsReadingIterator<CharT>    self_type;

  typedef ptrdiff_t                   difference_type;

  typedef size_t                      size_type;

  typedef CharT                       value_type;

  typedef const CharT*                pointer;

  typedef const CharT&                reference;

private:

  friend class mozilla::detail::nsTStringRepr<CharT>;

  // unfortunately, the API for nsReadingIterator requires that the

  // iterator know its start and end positions.  this was needed when

  // we supported multi-fragment strings, but now it is really just

  // extra baggage.  we should remove mStart and mEnd at some point.

  const CharT* mStart;

  const CharT* mEnd;

  const CharT* mPosition;

public:

  nsReadingIterator()

    : mStart(nullptr)

    , mEnd(nullptr)

    , mPosition(nullptr)

  {

  }

  // nsReadingIterator( const nsReadingIterator<CharT>& );                    // auto-generated copy-constructor OK

  // nsReadingIterator<CharT>& operator=( const nsReadingIterator<CharT>& );  // auto-generated copy-assignment operator OK

  pointer get() const

  {

    return mPosition;

  }

  CharT operator*() const

  {

    return *get();

  }

nsReadingIterator<char>::operator*() const

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Source

57

23.3M

  {

58

23.3M

    return *get();

59

23.3M

  }

nsReadingIterator<char16_t>::operator*() const

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Source

57

3.09M

  {

58

3.09M

    return *get();

59

3.09M

  }

  self_type& operator++()

  {

    ++mPosition;

    return *this;

  }

  self_type operator++(int)

  {

    self_type result(*this);

    ++mPosition;

    return result;

  }

nsReadingIterator<char>::operator++(int)

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68

15.7M

  {

69

15.7M

    self_type result(*this);

70

15.7M

    ++mPosition;

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15.7M

    return result;

72

15.7M

  }

nsReadingIterator<char16_t>::operator++(int)

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Source

68

3.09M

  {

69

3.09M

    self_type result(*this);

70

3.09M

    ++mPosition;

71

3.09M

    return result;

72

3.09M

  }

  self_type& operator--()

  {

    --mPosition;

    return *this;

  }

  self_type operator--(int)

  {

    self_type result(*this);

    --mPosition;

    return result;

  }

Unexecuted instantiation: nsReadingIterator<char16_t>::operator--(int)

Unexecuted instantiation: nsReadingIterator<char>::operator--(int)

  self_type& advance(difference_type aN)

  {

    if (aN > 0) {

      difference_type step = XPCOM_MIN(aN, mEnd - mPosition);

      NS_ASSERTION(step > 0,

                   "can't advance a reading iterator beyond the end of a string");

      mPosition += step;

    } else if (aN < 0) {

      difference_type step = XPCOM_MAX(aN, -(mPosition - mStart));

      NS_ASSERTION(step < 0,

                   "can't advance (backward) a reading iterator beyond the end of a string");

      mPosition += step;

    }

    return *this;

  }

  // We return an unsigned type here (with corresponding assert) rather than

  // the more usual difference_type because we want to make this class go

  // away in favor of mozilla::RangedPtr.  Since RangedPtr has the same

  // requirement we are enforcing here, the transition ought to be much

  // smoother.

  size_type operator-(const self_type& aOther) const

  {

    MOZ_ASSERT(mPosition >= aOther.mPosition);

    return mPosition - aOther.mPosition;

  }

Unexecuted instantiation: nsReadingIterator<char>::operator-(nsReadingIterator<char> const&) const

Unexecuted instantiation: nsReadingIterator<char16_t>::operator-(nsReadingIterator<char16_t> const&) const

};

template <class CharT>

inline bool

operator==(const nsReadingIterator<CharT>& aLhs,

           const nsReadingIterator<CharT>& aRhs)

{

  return aLhs.get() == aRhs.get();

}

template <class CharT>

inline bool

operator!=(const nsReadingIterator<CharT>& aLhs,

           const nsReadingIterator<CharT>& aRhs)

{

  return aLhs.get() != aRhs.get();

}

#endif /* !defined(nsStringIterator_h___) */