cxxomfort-examples

cxxomfort-examples

Examples for using the cxxomfort backports library

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This is a set of usage examples for cxxomfort, the backports library for C++, intended both as a demonstration of the working features and as a provision of code samples when pointing users to the library.

Instructions

Have the cxxomfort library (version with CXXOMFORT_DATE >= 20210101) installed. Pick the example you want and compile.

In order to work correctly, you can do any of the following:

• Copy or link the cxxomfort/ directory of the distribution into your compiler's system search path (/usr/local/include/ or similar).
• Add the path with -I /path/to/cxxomfort, or the equivalent option for your compiler / project.

Current Examples

The listing of examples includes but is not limited to:

1.- Showing information about cxxomfort and support.

• 0info.cpp - shows basic information, in particular detected compiler setup.
• 0showsupport.cpp - besides the above, shows specific information about features detected and supported by the library.

2.- Basic demonstrations - flexing one feature at a time.

• algorithms.cpp - simple showcase of some of the features in <algorithm>.
• any.cpp - C++17's std::any backport (needs the vocabulary extension).
• byte17.cpp - C++17's std::byte backport, showcasing the usage of the byte type, and initialization before C++17's rules.
• decay.cpp - C++11's std::decay type transformation.
• endian.cpp - C++20's std::endian backport, showing architecture-specific information.
• gcd.cpp - std::gcd and the pre-C++14 static version static_gcd part of cxxomfort:library.
• generic_errors.cpp - showcases the C++11 <system_error> features.
• make_array.cpp - shows experimental's make_array, which didn't make it to Standard before to_array() was introduced but is still useful for pre-C++17 code.
• optional.cpp - C++17's std::optional backport (needs the vocabulary extension).
• randonly.cpp - example use of utilities related to <random> as well as iterator accessors.
• plus.cpp - backports of C++14's "heterogeneous functors" (plus<void> and the like), as well as foreach emulation.
• string_helpers - showcases the use of cxxomfort's nonmember string helpers, for compatibility of strings-related code before and after C++20's extensions.
• string_view.cpp - backports of C++17's string_view utility, as well as showing related helpers.
• to_string.cpp - C++11's to_string backport.
• tuple_get.cpp - tuple<type> access elements by type, as well as testing features such as static_assert.

3.- Showcasing libraries and supplementals.

• explicit_cast.cpp - explicit_cast and explicit conversion operator emulation.
• foreach.cpp - foreach loop emulation feature (equivalent to for (v : sequence) { ... }), part of cxxomfort:library; among other things.
• to_string-variadic.cpp - extended variadic to_string proposal (p0117r0) in cxxomfort:library.
• tuple_pop.cpp - showcases cxxomfort's push, pop and shift operations for tuples.
• type_name.cpp cxxomfort:library's typeid_demangle() and type_name<> utilities.
• typesafe_enum.cpp showcases the typesafe enum implementation, an alternative to C++11's enum class.

4.- Examples adapted from external sources.

The examples in examples/cppref and examples/cplusplus have been adapted from the cppreference and cplusplus sites for use with cxxomfort. For exmple but not limited to:

• invoke.cpp - the std::invoke example showcasing invocation of functions and function objects.
• midpoint.cpp - the std::midpoint example for the new C++20 utility.
• typeindex.cpp - std::type_index and its use in hashes.
• unique_ptr.cpp - the unique_ptr<> example lifted from cppreference / cplusplus.

Notes

Testing Environments

Unless specified otherwise in any of the source files, these examples have been tested in most or all of the following environments:

• GCC 4.8 in C++03 mode.
• GCC 4.8 with --std=c++0x / --std=c++11.
• GCC 6.0 in C++11 mode.
• MSVC 2012 Express.
• Clang 4.0 in C++11 mode.
• Clang 6.0 in C++11 and C++14 mode.

All compiler configurations and limitations apply as per cxxomfort manual's Per-Compiler Notes.

For more information read cxxomfort configuration.