lite xformat - A C++ printf/scanf style IO library

Modules
	xprintf Family of Functions
	xscanf Family of Functions
	String Conversion
	Exceptions

---

Detailed Description

This is a header only library that provides functions for prinf/scanf style IO using iostreams. It also provides tool for conversion of values to/from strings.

Rationale

The following are the design goals for xprintf() / xscanf() :

• The syntax should be intuitive and should resemble the printf()/scanf() syntax as much as possible but without sacrificing usability or performance.
• The added overhead should be as minimal as possible.
• The format string should provide the possibility of adding user defined format fields.

Performance

In order to achieve a good performance the following has been done:

• The creation/destruction of sentry objects are minimized because they usually contain lock() / unlock() call to ensure thread safety.
• Retrieving locale and facets from the streams are minimized because the functions that retrieve these objects usually contain lock() / unlock() calls. To achieve this, the stream locale and all the necessary facets, and locale specific characters are retained in a cache object that is associated with each stream object. The cache object is updated using an stream event handler.
• There is only one extra virtual function call per each argument. This is to allow for more inlining of function calls.
• The basic_conversion class maintains an stream object. This avoids repeated construction/destruction of the stream object per each conversion and thus avoids a lot of unnecessary overhead when performing a large number of conversions (e.g., when reading an input file).

Benchmarks

Using the xprintf() / xscanf() functions are about 5 times faster that using the boost::format

Todo:

Add detailed benchmark