Parsing natural languages isn't easy. Just think about the ways to parse:

    Time flies like an arrow.
[download]

If you want to parse English, go get a linguistics degree at a University.

However, for a game you can get away with something else. Parsing simple sentences, which are often of the form:

    VERB [OBJECT [OBJECT]]
[download]

Text based games have been around for over three decades, including Collossal Cave, Zork and thousands of muds. For many games, source is available, and mudlibs are available too. Granted, they are typically written in another language than Perl, but that shouldn't be a problem. The algorithms will remain the same, and they'll be much easier to implement in Perl than in C or Fortran.

Abigail