6.1. Why Have Extensions

Why do we need extensions? Well, there are a number of reasons,
although not all of these are very good reasons:

·    Adaptations to new environments may require new functionality
  in order to easily interface to the operating system.

·    Extending the language with more power, to facilitate
  programming.

·    Sometimes, a lot of time can be saved if certain assumptions
  are met, so an extension might be implemented to allow programmers
  to take shortcuts.

·    When a program is ported from one platform to another, parts
  of the code may depend of non-standard features not available on
  the platform being ported to. In this situation, the availability
  of extensions that implement the feature may be of great help to
  the programmer.

·    The implementor had some good idea during development.

Extensions arise from holes in the functionality. Whether they
will survive or not depends on how they are perceived by
programmers; if perceived as useful, they will probably be used
and thus supported in more interpreters.



 PREV   NEXT