Mathex (Mathematical Expressions) is a specification and set of libraries for evaluating mathematical expressions from strings at runtime. It aims to provide consistent, customizable and easy to use solution for making your number fields more user friendly.
The specification defines valid expression syntax, feature set and error handling that a library implementing this specification must adhere to.
If you want to use Mathex in your project, here is a list of existing implementations of the specification:
Specification is stored in this repository in versions directory. There you can find the latest version of the specification, and some older ones.