## Source code

This page briefly describes the contents of the source files.

**Parser.java**

The class *Parser* is the core of the expression parser. This class contains the code required for parsing a string containing a mathematical expression, and evaluating the contents. This class contains a main routine, so you can run this class from a command line by entering "java Parser"

**Functions.java**

These files contain two mathematical functions which are not pre-defined in Java, and therefore had to be written by hand: factorial and sign.

**Error.java**

When an error occurs when parsing an expression, an error of class *Error* is thrown. All possible error messages are stored in the class Error, to make it easy to extend the parser to support multiple languages. All errors have a unique number.