Polymorphic Programming Language

The Polymorphic Programming Language (PPL) was developed in 1969 at Harvard University by Thomas A. Standish. It is an interactive, extensible language with a base language similar to APL.

The '<-' (or '←') assignment operator has played an influence in the S programming language.^[1]

References

• T.A. Standish. 1969. "Some features of PPL — a Polymorphic Programming Language". Proceedings of Extensible Language Symposium. Christensen and Shaw, Eds. SIGPLAN Notices, Vol 4, Aug. 1969.

1. ↑ Chambers, John M. (November 1994), Evolution of the S Language (PostScript), retrieved 2009-05-06