tinyformat.h

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// tinyformat.h
// Copyright (C) 2011, Chris Foster [chris42f (at) gmail (d0t) com]
//
// Boost Software License - Version 1.0
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
//
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
 
//------------------------------------------------------------------------------
// Tinyformat: A minimal type safe printf replacement
//
// tinyformat.h is a type safe printf replacement library in a single C++
// header file.  Design goals include:
//
// * Type safety and extensibility for user defined types.
// * C99 printf() compatibility, to the extent possible using std::ostream
// * POSIX extension for positional arguments
// * Simplicity and minimalism.  A single header file to include and distribute
//   with your projects.
// * Augment rather than replace the standard stream formatting mechanism
// * C++98 support, with optional C++11 niceties
//
//
// Main interface example usage
// ----------------------------
//
// To print a date to std::cout for American usage:
//
//   std::string weekday = "Wednesday";
//   const char* month = "July";
//   size_t day = 27;
//   long hour = 14;
//   int min = 44;
//
//   tfm::printf("%s, %s %d, %.2d:%.2d\n", weekday, month, day, hour, min);
//
// POSIX extension for positional arguments is available.
// The ability to rearrange formatting arguments is an important feature
// for localization because the word order may vary in different languages.
//
// Previous example for German usage. Arguments are reordered:
//
//   tfm::printf("%1$s, %3$d. %2$s, %4$d:%5$.2d\n", weekday, month, day, hour,
//   min);
//
// The strange types here emphasize the type safety of the interface; it is
// possible to print a std::string using the "%s" conversion, and a
// size_t using the "%d" conversion.  A similar result could be achieved
// using either of the tfm::format() functions.  One prints on a user provided
// stream:
//
//   tfm::format(std::cerr, "%s, %s %d, %.2d:%.2d\n",
//               weekday, month, day, hour, min);
//
// The other returns a std::string:
//
//   std::string date = tfm::format("%s, %s %d, %.2d:%.2d\n",
//                                  weekday, month, day, hour, min);
//   std::cout << date;
//
// These are the three primary interface functions.  There is also a
// convenience function printfln() which appends a newline to the usual result
// of printf() for super simple logging.
//
//
// User defined format functions
// -----------------------------
//
// Simulating variadic templates in C++98 is pretty painful since it requires
// writing out the same function for each desired number of arguments.  To make
// this bearable tinyformat comes with a set of macros which are used
// internally to generate the API, but which may also be used in user code.
//
// The three macros TINYFORMAT_ARGTYPES(n), TINYFORMAT_VARARGS(n) and
// TINYFORMAT_PASSARGS(n) will generate a list of n argument types,
// type/name pairs and argument names respectively when called with an integer
// n between 1 and 16.  We can use these to define a macro which generates the
// desired user defined function with n arguments.  To generate all 16 user
// defined function bodies, use the macro TINYFORMAT_FOREACH_ARGNUM.  For an
// example, see the implementation of printf() at the end of the source file.
//
// Sometimes it's useful to be able to pass a list of format arguments through
// to a non-template function.  The FormatList class is provided as a way to do
// this by storing the argument list in a type-opaque way.  Continuing the
// example from above, we construct a FormatList using makeFormatList():
//
//   FormatListRef formatList = tfm::makeFormatList(weekday, month, day, hour,
//   min);
//
// The format list can now be passed into any non-template function and used
// via a call to the vformat() function:
//
//   tfm::vformat(std::cout, "%s, %s %d, %.2d:%.2d\n", formatList);
//
//
// Additional API information
// --------------------------
//
// Error handling: Define TINYFORMAT_ERROR to customize the error handling for
// format strings which are unsupported or have the wrong number of format
// specifiers (calls assert() by default).
//
// User defined types: Uses operator<< for user defined types by default.
// Overload formatValue() for more control.
 
#ifndef TINYFORMAT_H_INCLUDED
#define TINYFORMAT_H_INCLUDED
 
namespace tinyformat {}
//------------------------------------------------------------------------------
// Config section.  Customize to your liking!
 
// Namespace alias to encourage brevity
namespace tfm = tinyformat;
 
// Error handling; calls assert() by default.
#define TINYFORMAT_ERROR(reasonString)                                         \
    throw tinyformat::format_error(reasonString)
 
// Define for C++11 variadic templates which make the code shorter & more
// general.  If you don't define this, C++11 support is autodetected below.
#define TINYFORMAT_USE_VARIADIC_TEMPLATES
 
//------------------------------------------------------------------------------
// Implementation details.
#include <algorithm>
#include <iostream>
#include <sstream>
#include <stdexcept> // Added for Bitcoin
 
#ifndef TINYFORMAT_ASSERT
#include <cassert>
#define TINYFORMAT_ASSERT(cond) assert(cond)
#endif
 
#ifndef TINYFORMAT_ERROR
#include <cassert>
#define TINYFORMAT_ERROR(reason) assert(0 && reason)
#endif
 
#if !defined(TINYFORMAT_USE_VARIADIC_TEMPLATES) &&                             \
    !defined(TINYFORMAT_NO_VARIADIC_TEMPLATES)
#ifdef __GXX_EXPERIMENTAL_CXX0X__
#define TINYFORMAT_USE_VARIADIC_TEMPLATES
#endif
#endif
 
#if defined(__GLIBCXX__) && __GLIBCXX__ < 20080201
//  std::showpos is broken on old libstdc++ as provided with macOS.  See
//  http://gcc.gnu.org/ml/libstdc++/2007-11/msg00075.html
#define TINYFORMAT_OLD_LIBSTDCPLUSPLUS_WORKAROUND
#endif
 
#ifdef __APPLE__
// Workaround macOS linker warning: Xcode uses different default symbol
// visibilities for static libs vs executables (see issue #25)
#define TINYFORMAT_HIDDEN __attribute__((visibility("hidden")))
#else
#define TINYFORMAT_HIDDEN
#endif
 
namespace tinyformat {
 
// Added for Bitcoin
class format_error : public std::runtime_error {
public:
    explicit format_error(const std::string &what) : std::runtime_error(what) {}
};
 
//------------------------------------------------------------------------------
namespace detail {
 
    // Test whether type T1 is convertible to type T2
    template <typename T1, typename T2> struct is_convertible {
    private:
        // two types of different size
        struct fail {
            char dummy[2];
        };
        struct succeed {
            char dummy;
        };
        // Try to convert a T1 to a T2 by plugging into tryConvert
        static fail tryConvert(...);
        static succeed tryConvert(const T2 &);
        static const T1 &makeT1();
 
    public:
#ifdef _MSC_VER
// Disable spurious loss of precision warnings in tryConvert(makeT1())
#pragma warning(push)
#pragma warning(disable : 4244)
#pragma warning(disable : 4267)
#endif
        // Standard trick: the (...) version of tryConvert will be chosen from
        // the overload set only if the version taking a T2 doesn't match. Then
        // we compare the sizes of the return types to check which function
        // matched.  Very neat, in a disgusting kind of way :)
        static const bool value =
            sizeof(tryConvert(makeT1())) == sizeof(succeed);
#ifdef _MSC_VER
#pragma warning(pop)
#endif
    };
 
    // Detect when a type is not a wchar_t string
    template <typename T> struct is_wchar {
        typedef int tinyformat_wchar_is_not_supported;
    };
    template <> struct is_wchar<wchar_t *> {};
    template <> struct is_wchar<const wchar_t *> {};
    template <int n> struct is_wchar<const wchar_t[n]> {};
    template <int n> struct is_wchar<wchar_t[n]> {};
 
    // Format the value by casting to type fmtT. This default implementation
    // should never be called.
    template <typename T, typename fmtT,
              bool convertible = is_convertible<T, fmtT>::value>
    struct formatValueAsType {
        static void invoke(std::ostream & /*out*/, const T & /*value*/) {
            TINYFORMAT_ASSERT(0);
        }
    };
    // Specialized version for types that can actually be converted to fmtT, as
    // indicated by the "convertible" template parameter.
    template <typename T, typename fmtT>
    struct formatValueAsType<T, fmtT, true> {
        static void invoke(std::ostream &out, const T &value) {
            out << static_cast<fmtT>(value);
        }
    };
 
#ifdef TINYFORMAT_OLD_LIBSTDCPLUSPLUS_WORKAROUND
    template <typename T, bool convertible = is_convertible<T, int>::value>
    struct formatZeroIntegerWorkaround {
        static bool invoke(std::ostream & , const T & ) {
            return false;
        }
    };
    template <typename T> struct formatZeroIntegerWorkaround<T, true> {
        static bool invoke(std::ostream &out, const T &value) {
            if (static_cast<int>(value) == 0 &&
                out.flags() & std::ios::showpos) {
                out << "+0";
                return true;
            }
            return false;
        }
    };
#endif // TINYFORMAT_OLD_LIBSTDCPLUSPLUS_WORKAROUND
 
    // Convert an arbitrary type to integer.  The version with convertible=false
    // throws an error.
    template <typename T, bool convertible = is_convertible<T, int>::value>
    struct convertToInt {
        static int invoke(const T & /*value*/) {
            TINYFORMAT_ERROR("tinyformat: Cannot convert from argument type to "
                             "integer for use as variable width or precision");
            return 0;
        }
    };
    // Specialization for convertToInt when conversion is possible
    template <typename T> struct convertToInt<T, true> {
        static int invoke(const T &value) { return static_cast<int>(value); }
    };
 
    // Format at most ntrunc characters to the given stream.
    template <typename T>
    inline void formatTruncated(std::ostream &out, const T &value, int ntrunc) {
        std::ostringstream tmp;
        tmp << value;
        std::string result = tmp.str();
        out.write(result.c_str(),
                  (std::min)(ntrunc, static_cast<int>(result.size())));
    }
#define TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR(type)                          \
    inline void formatTruncated(std::ostream &out, type *value, int ntrunc) {  \
        std::streamsize len = 0;                                               \
        while (len < ntrunc && value[len] != 0)                                \
            ++len;                                                             \
        out.write(value, len);                                                 \
    }
    // Overload for const char* and char*. Could overload for signed & unsigned
    // char too, but these are technically unneeded for printf compatibility.
    TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR(const char)
    TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR(char)
#undef TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR
 
} // namespace detail
 
//------------------------------------------------------------------------------
// Variable formatting functions.  May be overridden for user-defined types if
// desired.
 
template <typename T>
inline void formatValue(std::ostream &out, const char * /*fmtBegin*/,
                        const char *fmtEnd, int ntrunc, const T &value) {
#ifndef TINYFORMAT_ALLOW_WCHAR_STRINGS
    // Since we don't support printing of wchar_t using "%ls", make it fail at
    // compile time in preference to printing as a void* at runtime.
    typedef typename detail::is_wchar<T>::tinyformat_wchar_is_not_supported
        DummyType;
    (void)DummyType(); // avoid unused type warning with gcc-4.8
#endif
    // The mess here is to support the %c and %p conversions: if these
    // conversions are active we try to convert the type to a char or const
    // void* respectively and format that instead of the value itself. For the
    // %p conversion it's important to avoid dereferencing the pointer, which
    // could otherwise lead to a crash when printing a dangling (const char*).
    const bool canConvertToChar = detail::is_convertible<T, char>::value;
    const bool canConvertToVoidPtr =
        detail::is_convertible<T, const void *>::value;
    if (canConvertToChar && *(fmtEnd - 1) == 'c')
        detail::formatValueAsType<T, char>::invoke(out, value);
    else if (canConvertToVoidPtr && *(fmtEnd - 1) == 'p')
        detail::formatValueAsType<T, const void *>::invoke(out, value);
#ifdef TINYFORMAT_OLD_LIBSTDCPLUSPLUS_WORKAROUND
    else if (detail::formatZeroIntegerWorkaround<T>::invoke(out, value)) 
        ;
#endif
    else if (ntrunc >= 0) {
        // Take care not to overread C strings in truncating conversions like
        // "%.4s" where at most 4 characters may be read.
        detail::formatTruncated(out, value, ntrunc);
    } else
        out << value;
}
 
// Overloaded version for char types to support printing as an integer
#define TINYFORMAT_DEFINE_FORMATVALUE_CHAR(charType)                           \
    inline void formatValue(std::ostream &out, const char * /*fmtBegin*/,      \
                            const char *fmtEnd, int , charType value) {    \
        switch (*(fmtEnd - 1)) {                                               \
            case 'u':                                                          \
            case 'd':                                                          \
            case 'i':                                                          \
            case 'o':                                                          \
            case 'X':                                                          \
            case 'x':                                                          \
                out << static_cast<int>(value);                                \
                break;                                                         \
            default:                                                           \
                out << value;                                                  \
                break;                                                         \
        }                                                                      \
    }
// per 3.9.1: char, signed char and uint8_t are all distinct types
TINYFORMAT_DEFINE_FORMATVALUE_CHAR(char)
TINYFORMAT_DEFINE_FORMATVALUE_CHAR(signed char)
TINYFORMAT_DEFINE_FORMATVALUE_CHAR(uint8_t)
#undef TINYFORMAT_DEFINE_FORMATVALUE_CHAR
 
//------------------------------------------------------------------------------
// Tools for emulating variadic templates in C++98.  The basic idea here is
// stolen from the boost preprocessor metaprogramming library and cut down to
// be just general enough for what we need.
 
#define TINYFORMAT_ARGTYPES(n) TINYFORMAT_ARGTYPES_##n
#define TINYFORMAT_VARARGS(n) TINYFORMAT_VARARGS_##n
#define TINYFORMAT_PASSARGS(n) TINYFORMAT_PASSARGS_##n
#define TINYFORMAT_PASSARGS_TAIL(n) TINYFORMAT_PASSARGS_TAIL_##n
 
// To keep it as transparent as possible, the macros below have been generated
// using python via the excellent cog.py code generation script.  This avoids
// the need for a bunch of complex (but more general) preprocessor tricks as
// used in boost.preprocessor.
//
// To rerun the code generation in place, use `cog.py -r tinyformat.h`
// (see http://nedbatchelder.com/code/cog).  Alternatively you can just create
// extra versions by hand.
 
/*[[[cog
maxParams = 16
 
def makeCommaSepLists(lineTemplate, elemTemplate, startInd=1):
    for j in range(startInd,maxParams+1):
        list = ', '.join([elemTemplate % {'i':i} for i in range(startInd,j+1)])
        cog.outl(lineTemplate % {'j':j, 'list':list})
 
makeCommaSepLists('#define TINYFORMAT_ARGTYPES_%(j)d %(list)s',
                  'class T%(i)d')
 
cog.outl()
makeCommaSepLists('#define TINYFORMAT_VARARGS_%(j)d %(list)s',
                  'const T%(i)d& v%(i)d')
 
cog.outl()
makeCommaSepLists('#define TINYFORMAT_PASSARGS_%(j)d %(list)s', 'v%(i)d')
 
cog.outl()
cog.outl('#define TINYFORMAT_PASSARGS_TAIL_1')
makeCommaSepLists('#define TINYFORMAT_PASSARGS_TAIL_%(j)d , %(list)s',
                  'v%(i)d', startInd = 2)
 
cog.outl()
cog.outl('#define TINYFORMAT_FOREACH_ARGNUM(m) \\\n    ' +
         ' '.join(['m(%d)' % (j,) for j in range(1,maxParams+1)]))
]]]*/
#define TINYFORMAT_ARGTYPES_1 class T1
#define TINYFORMAT_ARGTYPES_2 class T1, class T2
#define TINYFORMAT_ARGTYPES_3 class T1, class T2, class T3
#define TINYFORMAT_ARGTYPES_4 class T1, class T2, class T3, class T4
#define TINYFORMAT_ARGTYPES_5 class T1, class T2, class T3, class T4, class T5
#define TINYFORMAT_ARGTYPES_6                                                  \
    class T1, class T2, class T3, class T4, class T5, class T6
#define TINYFORMAT_ARGTYPES_7                                                  \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7
#define TINYFORMAT_ARGTYPES_8                                                  \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8
#define TINYFORMAT_ARGTYPES_9                                                  \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9
#define TINYFORMAT_ARGTYPES_10                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10
#define TINYFORMAT_ARGTYPES_11                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10, class T11
#define TINYFORMAT_ARGTYPES_12                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10, class T11, class T12
#define TINYFORMAT_ARGTYPES_13                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10, class T11, class T12, class T13
#define TINYFORMAT_ARGTYPES_14                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10, class T11, class T12, class T13,        \
        class T14
#define TINYFORMAT_ARGTYPES_15                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10, class T11, class T12, class T13,        \
        class T14, class T15
#define TINYFORMAT_ARGTYPES_16                                                 \
    class T1, class T2, class T3, class T4, class T5, class T6, class T7,      \
        class T8, class T9, class T10, class T11, class T12, class T13,        \
        class T14, class T15, class T16
 
#define TINYFORMAT_VARARGS_1 const T1 &v1
#define TINYFORMAT_VARARGS_2 const T1 &v1, const T2 &v2
#define TINYFORMAT_VARARGS_3 const T1 &v1, const T2 &v2, const T3 &v3
#define TINYFORMAT_VARARGS_4                                                   \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4
#define TINYFORMAT_VARARGS_5                                                   \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5
#define TINYFORMAT_VARARGS_6                                                   \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6
#define TINYFORMAT_VARARGS_7                                                   \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7
#define TINYFORMAT_VARARGS_8                                                   \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8
#define TINYFORMAT_VARARGS_9                                                   \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9
#define TINYFORMAT_VARARGS_10                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9, const T10 &v10
#define TINYFORMAT_VARARGS_11                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9,                \
        const T10 &v10, const T11 &v11
#define TINYFORMAT_VARARGS_12                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9,                \
        const T10 &v10, const T11 &v11, const T12 &v12
#define TINYFORMAT_VARARGS_13                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9,                \
        const T10 &v10, const T11 &v11, const T12 &v12, const T13 &v13
#define TINYFORMAT_VARARGS_14                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9,                \
        const T10 &v10, const T11 &v11, const T12 &v12, const T13 &v13,        \
        const T14 &v14
#define TINYFORMAT_VARARGS_15                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9,                \
        const T10 &v10, const T11 &v11, const T12 &v12, const T13 &v13,        \
        const T14 &v14, const T15 &v15
#define TINYFORMAT_VARARGS_16                                                  \
    const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5,      \
        const T6 &v6, const T7 &v7, const T8 &v8, const T9 &v9,                \
        const T10 &v10, const T11 &v11, const T12 &v12, const T13 &v13,        \
        const T14 &v14, const T15 &v15, const T16 &v16
 
#define TINYFORMAT_PASSARGS_1 v1
#define TINYFORMAT_PASSARGS_2 v1, v2
#define TINYFORMAT_PASSARGS_3 v1, v2, v3
#define TINYFORMAT_PASSARGS_4 v1, v2, v3, v4
#define TINYFORMAT_PASSARGS_5 v1, v2, v3, v4, v5
#define TINYFORMAT_PASSARGS_6 v1, v2, v3, v4, v5, v6
#define TINYFORMAT_PASSARGS_7 v1, v2, v3, v4, v5, v6, v7
#define TINYFORMAT_PASSARGS_8 v1, v2, v3, v4, v5, v6, v7, v8
#define TINYFORMAT_PASSARGS_9 v1, v2, v3, v4, v5, v6, v7, v8, v9
#define TINYFORMAT_PASSARGS_10 v1, v2, v3, v4, v5, v6, v7, v8, v9, v10
#define TINYFORMAT_PASSARGS_11 v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11
#define TINYFORMAT_PASSARGS_12 v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12
#define TINYFORMAT_PASSARGS_13                                                 \
    v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13
#define TINYFORMAT_PASSARGS_14                                                 \
    v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14
#define TINYFORMAT_PASSARGS_15                                                 \
    v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15
#define TINYFORMAT_PASSARGS_16                                                 \
    v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16
 
#define TINYFORMAT_PASSARGS_TAIL_1
#define TINYFORMAT_PASSARGS_TAIL_2 , v2
#define TINYFORMAT_PASSARGS_TAIL_3 , v2, v3
#define TINYFORMAT_PASSARGS_TAIL_4 , v2, v3, v4
#define TINYFORMAT_PASSARGS_TAIL_5 , v2, v3, v4, v5
#define TINYFORMAT_PASSARGS_TAIL_6 , v2, v3, v4, v5, v6
#define TINYFORMAT_PASSARGS_TAIL_7 , v2, v3, v4, v5, v6, v7
#define TINYFORMAT_PASSARGS_TAIL_8 , v2, v3, v4, v5, v6, v7, v8
#define TINYFORMAT_PASSARGS_TAIL_9 , v2, v3, v4, v5, v6, v7, v8, v9
#define TINYFORMAT_PASSARGS_TAIL_10 , v2, v3, v4, v5, v6, v7, v8, v9, v10
#define TINYFORMAT_PASSARGS_TAIL_11 , v2, v3, v4, v5, v6, v7, v8, v9, v10, v11
#define TINYFORMAT_PASSARGS_TAIL_12                                            \
    , v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12
#define TINYFORMAT_PASSARGS_TAIL_13                                            \
    , v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13
#define TINYFORMAT_PASSARGS_TAIL_14                                            \
    , v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14
#define TINYFORMAT_PASSARGS_TAIL_15                                            \
    , v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15
#define TINYFORMAT_PASSARGS_TAIL_16                                            \
    , v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16
 
#define TINYFORMAT_FOREACH_ARGNUM(m)                                           \
    m(1) m(2) m(3) m(4) m(5) m(6) m(7) m(8) m(9) m(10) m(11) m(12) m(13) m(14) \
        m(15) m(16)
//[[[end]]]
 
namespace detail {
 
    // Type-opaque holder for an argument to format(), with associated actions
    // on the type held as explicit function pointers. This allows FormatArg's
    // for each argument to be allocated as a homogeneous array inside
    // FormatList whereas a naive implementation based on inheritance does not.
    class FormatArg {
    public:
        FormatArg() : m_value(NULL), m_formatImpl(NULL), m_toIntImpl(NULL) {}
 
        template <typename T>
        explicit FormatArg(const T &value)
            : m_value(static_cast<const void *>(&value)),
              m_formatImpl(&formatImpl<T>), m_toIntImpl(&toIntImpl<T>) {}
 
        void format(std::ostream &out, const char *fmtBegin, const char *fmtEnd,
                    int ntrunc) const {
            TINYFORMAT_ASSERT(m_value);
            TINYFORMAT_ASSERT(m_formatImpl);
            m_formatImpl(out, fmtBegin, fmtEnd, ntrunc, m_value);
        }
 
        int toInt() const {
            TINYFORMAT_ASSERT(m_value);
            TINYFORMAT_ASSERT(m_toIntImpl);
            return m_toIntImpl(m_value);
        }
 
    private:
        template <typename T>
        TINYFORMAT_HIDDEN static void
        formatImpl(std::ostream &out, const char *fmtBegin, const char *fmtEnd,
                   int ntrunc, const void *value) {
            formatValue(out, fmtBegin, fmtEnd, ntrunc,
                        *static_cast<const T *>(value));
        }
 
        template <typename T>
        TINYFORMAT_HIDDEN static int toIntImpl(const void *value) {
            return convertToInt<T>::invoke(*static_cast<const T *>(value));
        }
 
        const void *m_value;
        void (*m_formatImpl)(std::ostream &out, const char *fmtBegin,
                             const char *fmtEnd, int ntrunc, const void *value);
        int (*m_toIntImpl)(const void *value);
    };
 
    // Parse and return an integer from the string c, as atoi()
    // On return, c is set to one past the end of the integer.
    inline int parseIntAndAdvance(const char *&c) {
        int i = 0;
        for (; *c >= '0' && *c <= '9'; ++c)
            i = 10 * i + (*c - '0');
        return i;
    }
 
    // Parse width or precision `n` from format string pointer `c`, and advance
    // it to the next character. If an indirection is requested with `*`, the
    // argument is read from `args[argIndex]` and `argIndex` is incremented (or
    // read from `args[n]` in positional mode). Returns true if one or more
    // characters were read.
    inline bool parseWidthOrPrecision(int &n, const char *&c,
                                      bool positionalMode,
                                      const detail::FormatArg *args,
                                      int &argIndex, int numArgs) {
        if (*c >= '0' && *c <= '9') {
            n = parseIntAndAdvance(c);
        } else if (*c == '*') {
            ++c;
            n = 0;
            if (positionalMode) {
                int pos = parseIntAndAdvance(c) - 1;
                if (*c != '$')
                    TINYFORMAT_ERROR("tinyformat: Non-positional argument used "
                                     "after a positional one");
                if (pos >= 0 && pos < numArgs)
                    n = args[pos].toInt();
                else
                    TINYFORMAT_ERROR(
                        "tinyformat: Positional argument out of range");
                ++c;
            } else {
                if (argIndex < numArgs)
                    n = args[argIndex++].toInt();
                else
                    TINYFORMAT_ERROR("tinyformat: Not enough arguments to read "
                                     "variable width or precision");
            }
        } else {
            return false;
        }
        return true;
    }
 
    // Print literal part of format string and return next format spec position.
    //
    // Skips over any occurrences of '%%', printing a literal '%' to the output.
    // The position of the first % character of the next nontrivial format spec
    // is returned, or the end of string.
    inline const char *printFormatStringLiteral(std::ostream &out,
                                                const char *fmt) {
        const char *c = fmt;
        for (;; ++c) {
            if (*c == '\0') {
                out.write(fmt, c - fmt);
                return c;
            } else if (*c == '%') {
                out.write(fmt, c - fmt);
                if (*(c + 1) != '%') return c;
                // for "%%", tack trailing % onto next literal section.
                fmt = ++c;
            }
        }
    }
 
    // Parse a format string and set the stream state accordingly.
    //
    // The format mini-language recognized here is meant to be the one from C99,
    // with the form "%[flags][width][.precision][length]type" with POSIX
    // positional arguments extension.
    //
    // POSIX positional arguments extension:
    // Conversions can be applied to the nth argument after the format in
    // the argument list, rather than to the next unused argument. In this case,
    // the conversion specifier character % (see below) is replaced by the
    // sequence
    // "%n$", where n is a decimal integer in the range [1,{NL_ARGMAX}],
    // giving the position of the argument in the argument list. This feature
    // provides for the definition of format strings that select arguments
    // in an order appropriate to specific languages.
    //
    // The format can contain either numbered argument conversion specifications
    // (that is, "%n$" and "*m$"), or unnumbered argument conversion
    // specifications (that is, % and * ), but not both. The only exception to
    // this is that %% can be mixed with the "%n$" form. The results of mixing
    // numbered and unnumbered argument specifications in a format string are
    // undefined. When numbered argument specifications are used, specifying the
    // Nth argument requires that all the leading arguments, from the first to
    // the (N-1)th, are specified in the format string.
    //
    // In format strings containing the "%n$" form of conversion specification,
    // numbered arguments in the argument list can be referenced from the format
    // string as many times as required.
    //
    // Formatting options which can't be natively represented using the ostream
    // state are returned in spacePadPositive (for space padded positive
    // numbers) and ntrunc (for truncating conversions). argIndex is incremented
    // if necessary to pull out variable width and precision. The function
    // returns a pointer to the character after the end of the current format
    // spec.
    inline const char *streamStateFromFormat(std::ostream &out,
                                             bool &positionalMode,
                                             bool &spacePadPositive,
                                             int &ntrunc, const char *fmtStart,
                                             const detail::FormatArg *args,
                                             int &argIndex, int numArgs) {
        TINYFORMAT_ASSERT(*fmtStart == '%');
        // Reset stream state to defaults.
        out.width(0);
        out.precision(6);
        out.fill(' ');
        // Reset most flags; ignore irrelevant unitbuf & skipws.
        out.unsetf(std::ios::adjustfield | std::ios::basefield |
                   std::ios::floatfield | std::ios::showbase |
                   std::ios::boolalpha | std::ios::showpoint |
                   std::ios::showpos | std::ios::uppercase);
        bool precisionSet = false;
        bool widthSet = false;
        int widthExtra = 0;
        const char *c = fmtStart + 1;
 
        // 1) Parse an argument index (if followed by '$') or a width possibly
        // preceded with '0' flag.
        if (*c >= '0' && *c <= '9') {
            const char tmpc = *c;
            int value = parseIntAndAdvance(c);
            if (*c == '$') {
                // value is an argument index
                if (value > 0 && value <= numArgs)
                    argIndex = value - 1;
                else
                    TINYFORMAT_ERROR(
                        "tinyformat: Positional argument out of range");
                ++c;
                positionalMode = true;
            } else if (positionalMode) {
                TINYFORMAT_ERROR("tinyformat: Non-positional argument used "
                                 "after a positional one");
            } else {
                if (tmpc == '0') {
                    // Use internal padding so that numeric values are
                    // formatted correctly, eg -00010 rather than 000-10
                    out.fill('0');
                    out.setf(std::ios::internal, std::ios::adjustfield);
                }
                if (value != 0) {
                    // Nonzero value means that we parsed width.
                    widthSet = true;
                    out.width(value);
                }
            }
        } else if (positionalMode) {
            TINYFORMAT_ERROR("tinyformat: Non-positional argument used after a "
                             "positional one");
        }
        // 2) Parse flags and width if we did not do it in previous step.
        if (!widthSet) {
            // Parse flags
            for (;; ++c) {
                switch (*c) {
                    case '#':
                        out.setf(std::ios::showpoint | std::ios::showbase);
                        continue;
                    case '0':
                        // overridden by left alignment ('-' flag)
                        if (!(out.flags() & std::ios::left)) {
                            // Use internal padding so that numeric values are
                            // formatted correctly, eg -00010 rather than 000-10
                            out.fill('0');
                            out.setf(std::ios::internal, std::ios::adjustfield);
                        }
                        continue;
                    case '-':
                        out.fill(' ');
                        out.setf(std::ios::left, std::ios::adjustfield);
                        continue;
                    case ' ':
                        // overridden by show positive sign, '+' flag.
                        if (!(out.flags() & std::ios::showpos))
                            spacePadPositive = true;
                        continue;
                    case '+':
                        out.setf(std::ios::showpos);
                        spacePadPositive = false;
                        widthExtra = 1;
                        continue;
                    default:
                        break;
                }
                break;
            }
            // Parse width
            int width = 0;
            widthSet = parseWidthOrPrecision(width, c, positionalMode, args,
                                             argIndex, numArgs);
            if (widthSet) {
                if (width < 0) {
                    // negative widths correspond to '-' flag set
                    out.fill(' ');
                    out.setf(std::ios::left, std::ios::adjustfield);
                    width = -width;
                }
                out.width(width);
            }
        }
        // 3) Parse precision
        if (*c == '.') {
            ++c;
            int precision = 0;
            parseWidthOrPrecision(precision, c, positionalMode, args, argIndex,
                                  numArgs);
            // Presence of `.` indicates precision set, unless the inferred
            // value was negative in which case the default is used.
            precisionSet = precision >= 0;
            if (precisionSet) out.precision(precision);
        }
        // 4) Ignore any C99 length modifier
        while (*c == 'l' || *c == 'h' || *c == 'L' || *c == 'j' || *c == 'z' ||
               *c == 't') {
            ++c;
        }
        // 5) We're up to the conversion specifier character.
        // Set stream flags based on conversion specifier (thanks to the
        // boost::format class for forging the way here).
        bool intConversion = false;
        switch (*c) {
            case 'u':
            case 'd':
            case 'i':
                out.setf(std::ios::dec, std::ios::basefield);
                intConversion = true;
                break;
            case 'o':
                out.setf(std::ios::oct, std::ios::basefield);
                intConversion = true;
                break;
            case 'X':
                out.setf(std::ios::uppercase);
                // Falls through
            case 'x':
            case 'p':
                out.setf(std::ios::hex, std::ios::basefield);
                intConversion = true;
                break;
            case 'E':
                out.setf(std::ios::uppercase);
                // Falls through
            case 'e':
                out.setf(std::ios::scientific, std::ios::floatfield);
                out.setf(std::ios::dec, std::ios::basefield);
                break;
            case 'F':
                out.setf(std::ios::uppercase);
                // Falls through
            case 'f':
                out.setf(std::ios::fixed, std::ios::floatfield);
                break;
            case 'A':
                out.setf(std::ios::uppercase);
                // Falls through
            case 'a':
#ifdef _MSC_VER
                // Workaround
                // https://developercommunity.visualstudio.com/content/problem/520472/hexfloat-stream-output-does-not-ignore-precision-a.html
                // by always setting maximum precision on MSVC to avoid
                // precision loss for doubles.
                out.precision(13);
#endif
                out.setf(std::ios::fixed | std::ios::scientific,
                         std::ios::floatfield);
                break;
            case 'G':
                out.setf(std::ios::uppercase);
                // Falls through
            case 'g':
                out.setf(std::ios::dec, std::ios::basefield);
                // As in boost::format, let stream decide float format.
                out.flags(out.flags() & ~std::ios::floatfield);
                break;
            case 'c':
                // Handled as special case inside formatValue()
                break;
            case 's':
                if (precisionSet) ntrunc = static_cast<int>(out.precision());
                // Make %s print Booleans as "true" and "false"
                out.setf(std::ios::boolalpha);
                break;
            case 'n':
                // Not supported - will cause problems!
                TINYFORMAT_ERROR(
                    "tinyformat: %n conversion spec not supported");
                break;
            case '\0':
                TINYFORMAT_ERROR("tinyformat: Conversion spec incorrectly "
                                 "terminated by end of string");
                return c;
            default:
                break;
        }
        if (intConversion && precisionSet && !widthSet) {
            // "precision" for integers gives the minimum number of digits (to
            // be padded with zeros on the left). This isn't really supported by
            // the iostreams, but we can approximately simulate it with the
            // width if the width isn't otherwise used.
            out.width(out.precision() + widthExtra);
            out.setf(std::ios::internal, std::ios::adjustfield);
            out.fill('0');
        }
        return c + 1;
    }
 
    //------------------------------------------------------------------------------
    inline void formatImpl(std::ostream &out, const char *fmt,
                           const detail::FormatArg *args, int numArgs) {
        // Saved stream state
        std::streamsize origWidth = out.width();
        std::streamsize origPrecision = out.precision();
        std::ios::fmtflags origFlags = out.flags();
        char origFill = out.fill();
 
        // "Positional mode" means all format specs should be of the form
        // "%n$..." with `n` an integer. We detect this in
        // `streamStateFromFormat`.
        bool positionalMode = false;
        int argIndex = 0;
        while (true) {
            fmt = printFormatStringLiteral(out, fmt);
            if (*fmt == '\0') {
                if (!positionalMode && argIndex < numArgs) {
                    TINYFORMAT_ERROR("tinyformat: Not enough conversion "
                                     "specifiers in format string");
                }
                break;
            }
            bool spacePadPositive = false;
            int ntrunc = -1;
            const char *fmtEnd =
                streamStateFromFormat(out, positionalMode, spacePadPositive,
                                      ntrunc, fmt, args, argIndex, numArgs);
            // NB: argIndex may be incremented by reading variable
            // width/precision in `streamStateFromFormat`, so do the bounds
            // check here.
            if (argIndex >= numArgs) {
                TINYFORMAT_ERROR("tinyformat: Too many conversion specifiers "
                                 "in format string");
                return;
            }
            const FormatArg &arg = args[argIndex];
            // Format the arg into the stream.
            if (!spacePadPositive) {
                arg.format(out, fmt, fmtEnd, ntrunc);
            } else {
                // The following is a special case with no direct correspondence
                // between stream formatting and the printf() behaviour.
                // Simulate it crudely by formatting into a temporary string
                // stream and munging the resulting string.
                std::ostringstream tmpStream;
                tmpStream.copyfmt(out);
                tmpStream.setf(std::ios::showpos);
                arg.format(tmpStream, fmt, fmtEnd, ntrunc);
                std::string result = tmpStream.str(); // allocates... yuck.
                for (size_t i = 0, iend = result.size(); i < iend; ++i) {
                    if (result[i] == '+') result[i] = ' ';
                }
                out << result;
            }
            if (!positionalMode) ++argIndex;
            fmt = fmtEnd;
        }
 
        // Restore stream state
        out.width(origWidth);
        out.precision(origPrecision);
        out.flags(origFlags);
        out.fill(origFill);
    }
 
} // namespace detail
 
class FormatList {
public:
    FormatList(detail::FormatArg *args, int N) : m_args(args), m_N(N) {}
 
    friend void vformat(std::ostream &out, const char *fmt,
                        const FormatList &list);
 
private:
    const detail::FormatArg *m_args;
    int m_N;
};
 
typedef const FormatList &FormatListRef;
 
namespace detail {
 
    // Format list subclass with fixed storage to avoid dynamic allocation
    template <int N> class FormatListN : public FormatList {
    public:
#ifdef TINYFORMAT_USE_VARIADIC_TEMPLATES
        template <typename... Args>
        explicit FormatListN(const Args &...args)
            : FormatList(&m_formatterStore[0], N), m_formatterStore{
                                                       FormatArg(args)...} {
            static_assert(sizeof...(args) == N, "Number of args must be N");
        }
#else // C++98 version
        void init(int) {}
#define TINYFORMAT_MAKE_FORMATLIST_CONSTRUCTOR(n)                              \
                                                                               \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    FormatListN(TINYFORMAT_VARARGS(n)) : FormatList(&m_formatterStore[0], n) { \
        TINYFORMAT_ASSERT(n == N);                                             \
        init(0, TINYFORMAT_PASSARGS(n));                                       \
    }                                                                          \
                                                                               \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    void init(int i, TINYFORMAT_VARARGS(n)) {                                  \
        m_formatterStore[i] = FormatArg(v1);                                   \
        init(i + 1 TINYFORMAT_PASSARGS_TAIL(n));                               \
    }
 
        TINYFORMAT_FOREACH_ARGNUM(TINYFORMAT_MAKE_FORMATLIST_CONSTRUCTOR)
#undef TINYFORMAT_MAKE_FORMATLIST_CONSTRUCTOR
#endif
        FormatListN(const FormatListN &other)
            : FormatList(&m_formatterStore[0], N) {
            std::copy(&other.m_formatterStore[0], &other.m_formatterStore[N],
                      &m_formatterStore[0]);
        }
 
    private:
        FormatArg m_formatterStore[N];
    };
 
    // Special 0-arg version - MSVC says zero-sized C array in struct is
    // nonstandard.
    template <> class FormatListN<0> : public FormatList {
    public:
        FormatListN() : FormatList(0, 0) {}
    };
 
} // namespace detail
 
//------------------------------------------------------------------------------
// Primary API functions
 
#ifdef TINYFORMAT_USE_VARIADIC_TEMPLATES
 
template <typename... Args>
detail::FormatListN<sizeof...(Args)> makeFormatList(const Args &...args) {
    return detail::FormatListN<sizeof...(args)>(args...);
}
 
#else // C++98 version
 
inline detail::FormatListN<0> makeFormatList() {
    return detail::FormatListN<0>();
}
#define TINYFORMAT_MAKE_MAKEFORMATLIST(n)                                      \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    detail::FormatListN<n> makeFormatList(TINYFORMAT_VARARGS(n)) {             \
        return detail::FormatListN<n>(TINYFORMAT_PASSARGS(n));                 \
    }
TINYFORMAT_FOREACH_ARGNUM(TINYFORMAT_MAKE_MAKEFORMATLIST)
#undef TINYFORMAT_MAKE_MAKEFORMATLIST
 
#endif
 
inline void vformat(std::ostream &out, const char *fmt, FormatListRef list) {
    detail::formatImpl(out, fmt, list.m_args, list.m_N);
}
 
#ifdef TINYFORMAT_USE_VARIADIC_TEMPLATES
 
template <typename... Args>
void format(std::ostream &out, const char *fmt, const Args &...args) {
    vformat(out, fmt, makeFormatList(args...));
}
 
template <typename... Args>
std::string format(const char *fmt, const Args &...args) {
    std::ostringstream oss;
    format(oss, fmt, args...);
    return oss.str();
}
 
template <typename... Args> void printf(const char *fmt, const Args &...args) {
    format(std::cout, fmt, args...);
}
 
template <typename... Args>
void printfln(const char *fmt, const Args &...args) {
    format(std::cout, fmt, args...);
    std::cout << '\n';
}
 
#else // C++98 version
 
inline void format(std::ostream &out, const char *fmt) {
    vformat(out, fmt, makeFormatList());
}
 
inline std::string format(const char *fmt) {
    std::ostringstream oss;
    format(oss, fmt);
    return oss.str();
}
 
inline void printf(const char *fmt) {
    format(std::cout, fmt);
}
 
inline void printfln(const char *fmt) {
    format(std::cout, fmt);
    std::cout << '\n';
}
 
#define TINYFORMAT_MAKE_FORMAT_FUNCS(n)                                        \
                                                                               \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    void format(std::ostream &out, const char *fmt, TINYFORMAT_VARARGS(n)) {   \
        vformat(out, fmt, makeFormatList(TINYFORMAT_PASSARGS(n)));             \
    }                                                                          \
                                                                               \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    std::string format(const char *fmt, TINYFORMAT_VARARGS(n)) {               \
        std::ostringstream oss;                                                \
        format(oss, fmt, TINYFORMAT_PASSARGS(n));                              \
        return oss.str();                                                      \
    }                                                                          \
                                                                               \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    void printf(const char *fmt, TINYFORMAT_VARARGS(n)) {                      \
        format(std::cout, fmt, TINYFORMAT_PASSARGS(n));                        \
    }                                                                          \
                                                                               \
    template <TINYFORMAT_ARGTYPES(n)>                                          \
    void printfln(const char *fmt, TINYFORMAT_VARARGS(n)) {                    \
        format(std::cout, fmt, TINYFORMAT_PASSARGS(n));                        \
        std::cout << '\n';                                                     \
    }
 
TINYFORMAT_FOREACH_ARGNUM(TINYFORMAT_MAKE_FORMAT_FUNCS)
#undef TINYFORMAT_MAKE_FORMAT_FUNCS
 
#endif
 
// Added for Bitcoin
template <typename... Args>
std::string format(const std::string &fmt, const Args &...args) {
    std::ostringstream oss;
    format(oss, fmt.c_str(), args...);
    return oss.str();
}
 
} // namespace tinyformat
 
// Added for Bitcoin:
#define strprintf tfm::format
 
#endif // TINYFORMAT_H_INCLUDED