Source available on GitHub

Unformat

Parsing and extraction of original data from brace style "{}" formatted strings. It basically unformats what you thought was formatted for good.

Quick Example

Unformat is simple to use and works on all basic types. See the below example for extracting an ay::string_view and an int

ay::string_view name;
int age;

unformat("Harry is 18 years old.", "{} is {} years old.", name, age);
// name == "Harry" and age == 18

As an optimisation, if the format string is known at compile time, it can be parsed into a constant expression by making use of ay::make_format. In tests, this increases runtime speed by a factor of 3.

ay::string_view name;
int age;

constexpr auto format = ay::make_format("{} is {} years old.");
unformat("Harry is 18 years old.", format, name, age);
// name == "Harry" and age == 18

How do I use this library?

Unformat is a single-file header only library with zero dependencies (only <cstddef> for std::size_t). All you need to do is copy unformat.h into your project, and away you go.

ay::string_view is a simple non-owning struct containing a const char* data pointer and a std::size_t size. It can be converted to your own string type after parsing.

Public Domain

This software is completely open source and in the public domain. See LICENSE for details.

Contributing

Pull requests are very welcome. You may also create Issues and I will have a look into it as soon as I can.

Speed

Unformat is super awesome back to the future style lightning fast compared to traditional parsing methods. Below is the output from Google Benchmark on unformat_benchmark.cpp. Great Scott!

Run on (32 X 2420 MHz CPU s)
---------------------------------------------------------
Benchmark                                Time
---------------------------------------------------------
Unformat                              32.6 ns
Unformat_ConstexprMakeFormat          11.5 ns
StdStringStream                        391 ns
StdRegex                              3269 ns
StdScanf                               677 ns