Mathematical expressions are used by almost all applications. In fact, they are the foundation of programming languages. When you type a program, you are actually writing tons of math formulas. A program is static by nature, that is, it cannot be changed while executing. For example, a program written in C++ must be recompiled each time you change a single line of code. Hence, imagine that one math formula has to be modified in order to accommodate a change in the user environment. Do you like the idea of recompiling all your code just for one little formula change? There lies the usefulness of a math expression evaluator since it allows runtime formula evaluations and modifications without the need to change even one line of code. The trick is to handle math formulas as data instead of program instructions. The evaluator takes formulas as strings, compiles them on the fly, and computes the results that can be used transparently by your application.

Mathematic software is a mature field, and there are many excellent libraries available at minimal fees. Providing enhanced math functions and algorithms is thus not the primary mission of this parser. Instead, the focus is on allowing existing code to be reused in the context of run-time formula evaluation. For this purpose, the parser’s design defines a framework where existing functions can elegantly be integrated. Plug-in is the privileged way of extending the parser and, if you’ve developed one, I invite you to send me your component.

There are two parser versions: a native C++ library, and a COM component. The C++ library is highly extensible and fast, but its use is limited to the C++ language only. In counterpart, the COM component is easier to integrate in a project, and many programming languages can use it. COM plug-ins can be used to extend both the C++ library and the COM component.