776 lines
28 KiB
C++
776 lines
28 KiB
C++
// tinyformat.h
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// Copyright (C) 2011, Chris Foster [chris42f (at) gmail (d0t) com]
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//
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// Boost Software License - Version 1.0
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//
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// Permission is hereby granted, free of charge, to any person or organization
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// obtaining a copy of the software and accompanying documentation covered by
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// this license (the "Software") to use, reproduce, display, distribute,
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// execute, and transmit the Software, and to prepare derivative works of the
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// Software, and to permit third-parties to whom the Software is furnished to
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// do so, all subject to the following:
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//
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// The copyright notices in the Software and this entire statement, including
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// the above license grant, this restriction and the following disclaimer,
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// must be included in all copies of the Software, in whole or in part, and
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// all derivative works of the Software, unless such copies or derivative
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// works are solely in the form of machine-executable object code generated by
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// a source language processor.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
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// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
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// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
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// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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// DEALINGS IN THE SOFTWARE.
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//------------------------------------------------------------------------------
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// Tinyformat: A minimal type safe printf replacement
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//
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// tinyformat.h is a type safe printf replacement library in a single C++
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// header file. Design goals include:
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//
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// * Type safety and extensibility for user defined types.
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// * C99 printf() compatibility, to the extent possible using std::ostream
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// * Simplicity and minimalism. A single header file to include and distribute
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// with your projects.
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// * Augment rather than replace the standard stream formatting mechanism
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// * C++98 support, with optional C++11 niceties
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//
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//
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// Main interface example usage
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// ----------------------------
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//
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// To print a date to std::cout:
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//
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// std::string weekday = "Wednesday";
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// const char* month = "July";
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// size_t day = 27;
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// long hour = 14;
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// int min = 44;
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//
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// tfm::printf("%s, %s %d, %.2d:%.2d\n", weekday, month, day, hour, min);
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//
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// The strange types here emphasize the type safety of the interface; it is
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// possible to print a std::string using the "%s" conversion, and a
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// size_t using the "%d" conversion. A similar result could be achieved
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// using either of the tfm::format() functions. One prints on a user provided
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// stream:
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//
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// tfm::format(std::cerr, "%s, %s %d, %.2d:%.2d\n",
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// weekday, month, day, hour, min);
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//
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// The other returns a std::string:
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//
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// std::string date = tfm::format("%s, %s %d, %.2d:%.2d\n",
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// weekday, month, day, hour, min);
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// std::cout << date;
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//
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// These are the three primary interface functions. There is also a
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// convenience function printfln() which appends a newline to the usual result
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// of printf() for super simple logging.
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//
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//
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// User defined format functions
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// -----------------------------
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//
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// Sometimes it's useful to be able to pass a list of format arguments through
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// to a non-template function. The FormatList class is provided as a way to do
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// this by storing the argument list in a type-opaque way. Continuing the
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// example from above, we construct a FormatList using makeFormatList():
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//
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// FormatListRef formatList = tfm::makeFormatList(weekday, month, day, hour, min);
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//
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// The format list can now be passed into any non-template function and used
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// via a call to the vformat() function:
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//
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// tfm::vformat(std::cout, "%s, %s %d, %.2d:%.2d\n", formatList);
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//
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//
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// Additional API information
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// --------------------------
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//
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// Error handling: Define TINYFORMAT_ERROR to customize the error handling for
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// format strings which are unsupported or have the wrong number of format
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// specifiers (calls assert() by default).
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//
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// User defined types: Uses operator<< for user defined types by default.
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// Overload formatValue() for more control.
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#ifndef TINYFORMAT_H_INCLUDED
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#define TINYFORMAT_H_INCLUDED
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namespace tinyformat {}
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//------------------------------------------------------------------------------
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// Config section. Customize to your liking!
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// Namespace alias to encourage brevity
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namespace tfm = tinyformat;
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// Error handling; calls assert() by default.
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// #define TINYFORMAT_ERROR(reasonString) your_error_handler(reasonString)
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//------------------------------------------------------------------------------
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// Implementation details.
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#include <algorithm>
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#include <cassert>
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#include <iostream>
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#include <sstream>
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#ifndef TINYFORMAT_ERROR
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# define TINYFORMAT_ERROR(reason) assert(0 && reason)
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#endif
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#ifdef __APPLE__
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// Workaround OSX linker warning: xcode uses different default symbol
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// visibilities for static libs vs executables (see issue #25)
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# define TINYFORMAT_HIDDEN __attribute__((visibility("hidden")))
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#else
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# define TINYFORMAT_HIDDEN
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#endif
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#if defined(__clang__)
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# define TINYFORMAT_FALLTHROUGH [[clang::fallthrough]];
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#elif defined(__GNUG__) && __GNUC__ >= 7
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# define TINYFORMAT_FALLTHROUGH __attribute__ ((fallthrough));
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#else
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# define TINYFORMAT_FALLTHROUGH
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#endif
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namespace tinyformat {
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//------------------------------------------------------------------------------
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namespace detail {
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// Test whether type T1 is convertible to type T2
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template <typename T1, typename T2>
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struct is_convertible
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{
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private:
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// two types of different size
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struct fail { char dummy[2]; };
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struct succeed { char dummy; };
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// Try to convert a T1 to a T2 by plugging into tryConvert
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static fail tryConvert(...);
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static succeed tryConvert(const T2&);
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static const T1& makeT1();
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public:
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# ifdef _MSC_VER
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// Disable spurious loss of precision warnings in tryConvert(makeT1())
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# pragma warning(push)
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# pragma warning(disable:4244)
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# pragma warning(disable:4267)
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# endif
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// Standard trick: the (...) version of tryConvert will be chosen from
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// the overload set only if the version taking a T2 doesn't match.
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// Then we compare the sizes of the return types to check which
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// function matched. Very neat, in a disgusting kind of way :)
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static const bool value =
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sizeof(tryConvert(makeT1())) == sizeof(succeed);
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# ifdef _MSC_VER
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# pragma warning(pop)
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# endif
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};
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// Detect when a type is not a wchar_t string
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template<typename T> struct is_wchar { typedef int tinyformat_wchar_is_not_supported; };
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template<> struct is_wchar<wchar_t*> {};
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template<> struct is_wchar<const wchar_t*> {};
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template<int n> struct is_wchar<const wchar_t[n]> {};
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template<int n> struct is_wchar<wchar_t[n]> {};
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// Format the value by casting to type fmtT. This default implementation
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// should never be called.
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template<typename T, typename fmtT, bool convertible = is_convertible<T, fmtT>::value>
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struct formatValueAsType
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{
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static void invoke(std::ostream& /*out*/, const T& /*value*/) { assert(0); }
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};
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// Specialized version for types that can actually be converted to fmtT, as
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// indicated by the "convertible" template parameter.
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template<typename T, typename fmtT>
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struct formatValueAsType<T,fmtT,true>
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{
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static void invoke(std::ostream& out, const T& value)
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{ out << static_cast<fmtT>(value); }
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};
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// Convert an arbitrary type to integer. The version with convertible=false
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// throws an error.
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template<typename T, bool convertible = is_convertible<T,int>::value>
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struct convertToInt
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{
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static int invoke(const T& /*value*/)
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{
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TINYFORMAT_ERROR("tinyformat: Cannot convert from argument type to "
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"integer for use as variable width or precision");
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return 0;
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}
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};
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// Specialization for convertToInt when conversion is possible
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template<typename T>
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struct convertToInt<T,true>
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{
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static int invoke(const T& value) { return static_cast<int>(value); }
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};
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// Format at most ntrunc characters to the given stream.
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template<typename T>
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inline void formatTruncated(std::ostream& out, const T& value, int ntrunc)
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{
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std::ostringstream tmp;
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tmp << value;
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std::string result = tmp.str();
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out.write(result.c_str(), (std::min)(ntrunc, static_cast<int>(result.size())));
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}
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#define TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR(type) \
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inline void formatTruncated(std::ostream& out, type* value, int ntrunc) \
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{ \
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std::streamsize len = 0; \
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while(len < ntrunc && value[len] != 0) \
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++len; \
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out.write(value, len); \
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}
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// Overload for const char* and char*. Could overload for signed & unsigned
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// char too, but these are technically unneeded for printf compatibility.
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TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR(const char)
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TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR(char)
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#undef TINYFORMAT_DEFINE_FORMAT_TRUNCATED_CSTR
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} // namespace detail
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//------------------------------------------------------------------------------
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// Variable formatting functions. May be overridden for user-defined types if
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// desired.
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/// Format a value into a stream, delegating to operator<< by default.
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///
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/// Users may override this for their own types. When this function is called,
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/// the stream flags will have been modified according to the format string.
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/// The format specification is provided in the range [fmtBegin, fmtEnd). For
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/// truncating conversions, ntrunc is set to the desired maximum number of
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/// characters, for example "%.7s" calls formatValue with ntrunc = 7.
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///
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/// By default, formatValue() uses the usual stream insertion operator
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/// operator<< to format the type T, with special cases for the %c and %p
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/// conversions.
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template<typename T>
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inline void formatValue(std::ostream& out, const char* /*fmtBegin*/,
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const char* fmtEnd, int ntrunc, const T& value)
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{
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#ifndef TINYFORMAT_ALLOW_WCHAR_STRINGS
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// Since we don't support printing of wchar_t using "%ls", make it fail at
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// compile time in preference to printing as a void* at runtime.
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typedef typename detail::is_wchar<T>::tinyformat_wchar_is_not_supported DummyType;
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(void) DummyType(); // avoid unused type warning with gcc-4.8
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#endif
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// The mess here is to support the %c and %p conversions: if these
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// conversions are active we try to convert the type to a char or const
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// void* respectively and format that instead of the value itself. For the
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// %p conversion it's important to avoid dereferencing the pointer, which
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// could otherwise lead to a crash when printing a dangling (const char*).
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bool canConvertToChar = detail::is_convertible<T,char>::value;
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bool canConvertToVoidPtr = detail::is_convertible<T, const void*>::value;
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if(canConvertToChar && *(fmtEnd-1) == 'c')
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detail::formatValueAsType<T, char>::invoke(out, value);
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else if(canConvertToVoidPtr && *(fmtEnd-1) == 'p')
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detail::formatValueAsType<T, const void*>::invoke(out, value);
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else if(ntrunc >= 0)
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{
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// Take care not to overread C strings in truncating conversions like
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// "%.4s" where at most 4 characters may be read.
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detail::formatTruncated(out, value, ntrunc);
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}
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else
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out << value;
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}
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// Overloaded version for char types to support printing as an integer
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#define TINYFORMAT_DEFINE_FORMATVALUE_CHAR(charType) \
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inline void formatValue(std::ostream& out, const char* /*fmtBegin*/, \
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const char* fmtEnd, int /**/, charType value) \
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{ \
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switch(*(fmtEnd-1)) \
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{ \
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case 'u': case 'd': case 'i': case 'o': case 'X': case 'x': \
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out << static_cast<int>(value); break; \
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default: \
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out << value; break; \
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} \
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}
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// per 3.9.1: char, signed char and unsigned char are all distinct types
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TINYFORMAT_DEFINE_FORMATVALUE_CHAR(char)
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TINYFORMAT_DEFINE_FORMATVALUE_CHAR(signed char)
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TINYFORMAT_DEFINE_FORMATVALUE_CHAR(unsigned char)
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#undef TINYFORMAT_DEFINE_FORMATVALUE_CHAR
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namespace detail {
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// Type-opaque holder for an argument to format(), with associated actions on
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// the type held as explicit function pointers. This allows FormatArg's for
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// each argument to be allocated as a homogenous array inside FormatList
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// whereas a naive implementation based on inheritance does not.
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class FormatArg
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{
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public:
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FormatArg() {}
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template<typename T>
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FormatArg(const T& value)
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: m_value(static_cast<const void*>(&value)),
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m_formatImpl(&formatImpl<T>),
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m_toIntImpl(&toIntImpl<T>)
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{ }
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void format(std::ostream& out, const char* fmtBegin,
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const char* fmtEnd, int ntrunc) const
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{
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m_formatImpl(out, fmtBegin, fmtEnd, ntrunc, m_value);
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}
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int toInt() const
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{
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return m_toIntImpl(m_value);
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}
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private:
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template<typename T>
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TINYFORMAT_HIDDEN static void formatImpl(std::ostream& out, const char* fmtBegin,
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const char* fmtEnd, int ntrunc, const void* value)
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{
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formatValue(out, fmtBegin, fmtEnd, ntrunc, *static_cast<const T*>(value));
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}
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template<typename T>
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TINYFORMAT_HIDDEN static int toIntImpl(const void* value)
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{
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return convertToInt<T>::invoke(*static_cast<const T*>(value));
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}
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const void* m_value;
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void (*m_formatImpl)(std::ostream& out, const char* fmtBegin,
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const char* fmtEnd, int ntrunc, const void* value);
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int (*m_toIntImpl)(const void* value);
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};
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// Parse and return an integer from the string c, as atoi()
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// On return, c is set to one past the end of the integer.
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inline int parseIntAndAdvance(const char*& c)
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{
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int i = 0;
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for(;*c >= '0' && *c <= '9'; ++c)
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i = 10*i + (*c - '0');
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return i;
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}
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// Print literal part of format string and return next format spec
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// position.
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//
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// Skips over any occurrences of '%%', printing a literal '%' to the
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// output. The position of the first % character of the next
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// nontrivial format spec is returned, or the end of string.
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inline const char* printFormatStringLiteral(std::ostream& out, const char* fmt)
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{
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const char* c = fmt;
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for(;; ++c)
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{
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switch(*c)
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{
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case '\0':
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out.write(fmt, c - fmt);
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return c;
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case '%':
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out.write(fmt, c - fmt);
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if(*(c+1) != '%')
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return c;
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// for "%%", tack trailing % onto next literal section.
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fmt = ++c;
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break;
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default:
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break;
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}
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}
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}
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// Parse a format string and set the stream state accordingly.
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//
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// The format mini-language recognized here is meant to be the one from C99,
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// with the form "%[flags][width][.precision][length]type".
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//
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// Formatting options which can't be natively represented using the ostream
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// state are returned in spacePadPositive (for space padded positive numbers)
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// and ntrunc (for truncating conversions). argIndex is incremented if
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// necessary to pull out variable width and precision . The function returns a
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// pointer to the character after the end of the current format spec.
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inline const char* streamStateFromFormat(std::ostream& out, bool& spacePadPositive,
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int& ntrunc, const char* fmtStart,
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const detail::FormatArg* formatters,
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int& argIndex, int numFormatters)
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{
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if(*fmtStart != '%')
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{
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TINYFORMAT_ERROR("tinyformat: Not enough conversion specifiers in format string");
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return fmtStart;
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}
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// Reset stream state to defaults.
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out.width(0);
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out.precision(6);
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out.fill(' ');
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// Reset most flags; ignore irrelevant unitbuf & skipws.
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out.unsetf(std::ios::adjustfield | std::ios::basefield |
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std::ios::floatfield | std::ios::showbase | std::ios::boolalpha |
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std::ios::showpoint | std::ios::showpos | std::ios::uppercase);
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bool precisionSet = false;
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bool widthSet = false;
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int widthExtra = 0;
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const char* c = fmtStart + 1;
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// 1) Parse flags
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for(;; ++c)
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{
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switch(*c)
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{
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case '#':
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out.setf(std::ios::showpoint | std::ios::showbase);
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continue;
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case '0':
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// overridden by left alignment ('-' flag)
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if(!(out.flags() & std::ios::left))
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{
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// Use internal padding so that numeric values are
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// formatted correctly, eg -00010 rather than 000-10
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out.fill('0');
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out.setf(std::ios::internal, std::ios::adjustfield);
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}
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continue;
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case '-':
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out.fill(' ');
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out.setf(std::ios::left, std::ios::adjustfield);
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continue;
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case ' ':
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// overridden by show positive sign, '+' flag.
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if(!(out.flags() & std::ios::showpos))
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spacePadPositive = true;
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continue;
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case '+':
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out.setf(std::ios::showpos);
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spacePadPositive = false;
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widthExtra = 1;
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continue;
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default:
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break;
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}
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break;
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}
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// 2) Parse width
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if(*c >= '0' && *c <= '9')
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{
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widthSet = true;
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out.width(parseIntAndAdvance(c));
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}
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if(*c == '*')
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{
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widthSet = true;
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int width = 0;
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if(argIndex < numFormatters)
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width = formatters[argIndex++].toInt();
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else
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TINYFORMAT_ERROR("tinyformat: Not enough arguments to read variable width");
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if(width < 0)
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{
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// negative widths correspond to '-' flag set
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out.fill(' ');
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out.setf(std::ios::left, std::ios::adjustfield);
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width = -width;
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}
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out.width(width);
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++c;
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}
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// 3) Parse precision
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|
if(*c == '.')
|
|
{
|
|
++c;
|
|
int precision = 0;
|
|
if(*c == '*')
|
|
{
|
|
++c;
|
|
if(argIndex < numFormatters)
|
|
precision = formatters[argIndex++].toInt();
|
|
else
|
|
TINYFORMAT_ERROR("tinyformat: Not enough arguments to read variable precision");
|
|
}
|
|
else
|
|
{
|
|
if(*c >= '0' && *c <= '9')
|
|
precision = parseIntAndAdvance(c);
|
|
else if(*c == '-') // negative precisions ignored, treated as zero.
|
|
parseIntAndAdvance(++c);
|
|
}
|
|
out.precision(precision);
|
|
precisionSet = true;
|
|
}
|
|
// 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);
|
|
TINYFORMAT_FALLTHROUGH
|
|
case 'x': case 'p':
|
|
out.setf(std::ios::hex, std::ios::basefield);
|
|
intConversion = true;
|
|
break;
|
|
case 'E':
|
|
out.setf(std::ios::uppercase);
|
|
TINYFORMAT_FALLTHROUGH
|
|
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);
|
|
TINYFORMAT_FALLTHROUGH
|
|
case 'f':
|
|
out.setf(std::ios::fixed, std::ios::floatfield);
|
|
break;
|
|
case 'G':
|
|
out.setf(std::ios::uppercase);
|
|
TINYFORMAT_FALLTHROUGH
|
|
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 'a': case 'A':
|
|
TINYFORMAT_ERROR("tinyformat: the %a and %A conversion specs "
|
|
"are not supported");
|
|
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* formatters,
|
|
int numFormatters)
|
|
{
|
|
// Saved stream state
|
|
std::streamsize origWidth = out.width();
|
|
std::streamsize origPrecision = out.precision();
|
|
std::ios::fmtflags origFlags = out.flags();
|
|
char origFill = out.fill();
|
|
|
|
for (int argIndex = 0; argIndex < numFormatters; ++argIndex)
|
|
{
|
|
// Parse the format string
|
|
fmt = printFormatStringLiteral(out, fmt);
|
|
bool spacePadPositive = false;
|
|
int ntrunc = -1;
|
|
const char* fmtEnd = streamStateFromFormat(out, spacePadPositive, ntrunc, fmt,
|
|
formatters, argIndex, numFormatters);
|
|
if (argIndex >= numFormatters)
|
|
{
|
|
// Check args remain after reading any variable width/precision
|
|
TINYFORMAT_ERROR("tinyformat: Not enough format arguments");
|
|
return;
|
|
}
|
|
const FormatArg& arg = formatters[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;
|
|
}
|
|
fmt = fmtEnd;
|
|
}
|
|
|
|
// Print remaining part of format string.
|
|
fmt = printFormatStringLiteral(out, fmt);
|
|
if(*fmt != '\0')
|
|
TINYFORMAT_ERROR("tinyformat: Too many conversion specifiers in format string");
|
|
|
|
// Restore stream state
|
|
out.width(origWidth);
|
|
out.precision(origPrecision);
|
|
out.flags(origFlags);
|
|
out.fill(origFill);
|
|
}
|
|
|
|
} // namespace detail
|
|
|
|
|
|
/// List of template arguments format(), held in a type-opaque way.
|
|
///
|
|
/// A const reference to FormatList (typedef'd as FormatListRef) may be
|
|
/// conveniently used to pass arguments to non-template functions: All type
|
|
/// information has been stripped from the arguments, leaving just enough of a
|
|
/// common interface to perform formatting as required.
|
|
class FormatList
|
|
{
|
|
public:
|
|
FormatList(detail::FormatArg* formatters, int N)
|
|
: m_formatters(formatters), m_N(N) { }
|
|
|
|
friend void vformat(std::ostream& out, const char* fmt,
|
|
const FormatList& list);
|
|
|
|
private:
|
|
const detail::FormatArg* m_formatters;
|
|
int m_N;
|
|
};
|
|
|
|
/// Reference to type-opaque format list for passing to vformat()
|
|
typedef const FormatList& FormatListRef;
|
|
|
|
|
|
namespace detail {
|
|
|
|
// Format list subclass with fixed storage to avoid dynamic allocation
|
|
template<int N>
|
|
class FormatListN : public FormatList
|
|
{
|
|
public:
|
|
template<typename... Args>
|
|
FormatListN(const Args&... args)
|
|
: FormatList(&m_formatterStore[0], N),
|
|
m_formatterStore { FormatArg(args)... }
|
|
{ static_assert(sizeof...(args) == N, "Number of args must be N"); }
|
|
|
|
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
|
|
|
|
/// Make type-agnostic format list from list of template arguments.
|
|
///
|
|
/// The exact return type of this function is an implementation detail and
|
|
/// shouldn't be relied upon. Instead it should be stored as a FormatListRef:
|
|
///
|
|
/// FormatListRef formatList = makeFormatList( /*...*/ );
|
|
template<typename... Args>
|
|
detail::FormatListN<sizeof...(Args)> makeFormatList(const Args&... args)
|
|
{
|
|
return detail::FormatListN<sizeof...(args)>(args...);
|
|
}
|
|
|
|
/// Format list of arguments to the stream according to the given format string.
|
|
///
|
|
/// The name vformat() is chosen for the semantic similarity to vprintf(): the
|
|
/// list of format arguments is held in a single function argument.
|
|
inline void vformat(std::ostream& out, const char* fmt, FormatListRef list)
|
|
{
|
|
detail::formatImpl(out, fmt, list.m_formatters, list.m_N);
|
|
}
|
|
|
|
|
|
/// Format list of arguments to the stream according to given format string.
|
|
template<typename... Args>
|
|
void format(std::ostream& out, const char* fmt, const Args&... args)
|
|
{
|
|
vformat(out, fmt, makeFormatList(args...));
|
|
}
|
|
|
|
/// Format list of arguments according to the given format string and return
|
|
/// the result as a string.
|
|
template<typename... Args>
|
|
std::string format(const char* fmt, const Args&... args)
|
|
{
|
|
std::ostringstream oss;
|
|
format(oss, fmt, args...);
|
|
return oss.str();
|
|
}
|
|
|
|
/// Format list of arguments to std::cout, according to the given format string
|
|
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';
|
|
}
|
|
|
|
|
|
} // namespace tinyformat
|
|
|
|
#endif // TINYFORMAT_H_INCLUDED
|