63.1 ENT Basics

SXEmacs supports several of the available arithmetical and mathematical libraries. Wherever possible, it is attempted to introduce a transparency layer, such that one library can be exchanged by another when both provide equal or similar functionality. This layering allow emacs lisp and C programmers to minimise their efforts by using a standardised interface.

On the other hand, it is attempted to additionally bring all library-specific features into the emacs lisp environment. That way emacs lisp (and also C) programmers can easily use certain functions which are contained in only one specific library.

Some of the functionality provided by libraries is even re-implemented in C in order to allow emacs lisp programmers to use such functions even if the external library is not available. This may sound a little obscure, but it is important to establish a consistent and convenient concept of number types in the emacs lisp environment once the enhanced number type support is enabled.

We start this section with a quick overview of what is available out there, and what is additionally available due to re-implementation.