include/iomanip

/* -*- c++ -*- */
/*
 * Copyright (C) 2010 The Android Open Source Project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef ANDROID_ASTL_IOMANIP__
#define ANDROID_ASTL_IOMANIP__

#include <ostream>

// iomanips are structures used to manipulate streams. There are 3
// parts to a manip:
// - a struct to hold the parameters of the manip.
// - a function in the std namespace to generate the above structure.
// - a stream operator that takes the structure as second argument and
//   apply the manip using the params in the structure.
//
// This allows something like that : cout << setprecision(10);

namespace android {
// Structures passed to the streams to set various aspect of it.
struct SetBase { int base; };
struct SetPrecision { int precision; };
}

namespace std {

// Sent to a stream, calls 'precision(size_type)' on the instance.
inline android::SetPrecision setprecision(int precision) {
    android::SetPrecision params;
    params.precision = precision;
    return params;
}

inline ostream& operator<<(ostream& os, android::SetPrecision params) {
    os.precision(params.precision);
    return os;
}

// Sent to a stream, set the ios_base::basefield on the instance.
// Sent to a stream, calls 'precision(size_type)' on the instance.
inline android::SetBase setbase(int base) {
    android::SetBase params;
    params.base = base;
    return params;
}

inline ostream& operator<<(ostream& os, android::SetBase params) {
    os.setf(params.base == 8  ? ios_base::oct :
            params.base == 10 ? ios_base::dec :
            params.base == 16 ? ios_base::hex :
            ios_base::fmtflags(0), ios_base::basefield);
    return os;
}

}  // namespace std

#endif