Spar is a maths applications framework. This means that the Spar Library allow C/C++ programmers to write easily maths applications. The library supports a number of features, such as: plugins (modules), user variables, many common math functions, complex functions, error reporting, test and timing functions, vectors algebra, formula library, constants, and a complete IO library. However the lirary is not yet complete: integration, interpolation, geometry (and other) are missing. All Spar applications can be configured as you wish: infact,   you can request special features such as modules support and getopt support. Finally the library comes with a fully featured console calculator (is only a Spar application).

Spar, can be easily extended with modules. A module is a "user" extensions, written in C/C++, to the basic features of the Simple Parser. Here you can find the module definition: is a C structure that contains only few data member:
    - module name
    - module version  
    - module version
    - module descriptionn
    - a pointer to the module main function

The modules are loaded at run-time by the module loader (that is a high     level layer of the module manager): you can load your modules, simply,  coping  theirs paths into the .spar_modules (or any other file, with the -c option).  However there is only one module available and it's intended only for didacticals  purposes. Finally, here  you can find  a module template. As you can see is very simple create a Spar module: these new features is  available only with the last release of the Spar Library. 

The Spar console front end (aka spar) is a fully featured programs that     uses the Spar Library. It works as an interactive calculator (like bc, rascal and others). It's an  example  of the capabilities provided by the Spar Library: it's quite customizable and easy to use. Just try it! Here you can see a HTML version of the man page.