apl  1.6a
About: GNU APL is a free interpreter for the (ancient) programming language APL and an (almost) complete implementation of the ISO standard 13751.
  Fossies Dox: apl-1.6a.tar.gz  ("inofficial" and yet experimental doxygen-generated source code documentation)  

GNU APL

GNU APL is a free interpreter for the programming language APL.

GNU APL tries to be compatible with both the ISO standard 13751 (aka. Programming Language APL, Extended) and to IBM APL2.

It is NOT meant to be a vehicle for implementing new features to the APL language.