18 Dec 1996 00:08:36 -0500

Related articles |
---|

[3 earlier articles] |

Re: User definable operators mslamm@pluto.mscc.huji.ac.il (Ehud Lamm) (1996-12-15) |

Re: User definable operators ddean@CS.Princeton.EDU (1996-12-15) |

Re: User definable operators dennis@netcom.com (1996-12-15) |

Re: User definable operators fjh@mundook.cs.mu.OZ.AU (1996-12-15) |

Re: User definable operators burley@gnu.ai.mit.edu (Craig Burley) (1996-12-18) |

Re: User definable operators jdean@puma.pa.dec.com (1996-12-18) |

Re: User definable operators neitzel@gaertner.de (1996-12-18) |

Re: User definable operators tim@franck.Princeton.EDU (1996-12-20) |

Re: User definable operators nkramer@cs.cmu.edu (Nick Kramer) (1996-12-20) |

Re: User definable operators hrubin@stat.purdue.edu (1996-12-24) |

Re: User definable operators preston@tera.com (1996-12-26) |

Re: User definable operators burley@gnu.ai.mit.edu (Craig Burley) (1996-12-26) |

Re: User definable operators mfinney@inmind.com (1996-12-26) |

[10 later articles] |

From: | neitzel@gaertner.de (Martin Neitzel) |

Newsgroups: | comp.compilers |

Date: | 18 Dec 1996 00:08:36 -0500 |

Organization: | Gaertner Datensysteme, Braunschweig, Germany |

References: | 96-12-088 96-12-110 |

Keywords: | design, APL |

Charles Fiterman <cef@geodesic.com>:

*>In math it's name and conquer so people need to build their own symbols*

*>easily and use them easily.*

As an APL programmer, I have some comments on this specific "symbolistic"

view of operators.

* APL was devised as a substitute for standard mathematical notation.

"MN" has quite a bunch of inconsistencies and quirks. APL offers

a more systematic way to write mathmatics. Unlike Charles Fiterman

suggested, the power of APL comes often from _dropping_ special

symbols like large sigma and deriving their functionality from more

fundamental concepts (addition and "reduction": "+/"). Very often, this

leads to generalized notations: Where MN stops when it runs out of

special symbols Large Sigma and Large Pi, APL really takes off after

+/ and */ because the "reduction" is available (which is what Heaviside

would have called an "operator").

* APL is, uhm, "famous" for its graphical character set.

In the end, it died because such peculiar notations didn't

communicate well enough with new people.

* One of the recent APL dialects, J, is straight ASCII. J-ers usually

don't miss the distinct APL symbol kit after getting used to something that

might look like line noise from time to time. It's certainly a small

price for being able mail a program around which does not work in

terms of just Silly Scalars.

Definite classic references on APL vs. Mathematical Notation are contained

in IBM Systems Journal v30 n4 (1990 or 91).

Martin Neitzel

--

Post a followup to this message

Return to the
comp.compilers page.

Search the
comp.compilers archives again.