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Why APL Is Still Cool

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Re: Why APL Is Still Cool

#11

Post by bwanab »

T_S_ wrote: post #8

To me the biggest lesson from APL is to always try to manipulate the largest data structure you can your hands on. For example, don't think about for-loops, think about 'map'. When you can do that, life is good. The limitations of the language that I saw (in the mid 90s) were around interoperability. Devs saw it as esoteric and steered toward something more 'marketable' like C++ and later Java. The extensive use of m…

It was used heavily in the fixed income division. I was there during the phase out and among the A-Plus developers there was an "...out of my cold, dead hands" mentality. They (and there were a lot of them) really loved it.

Re: Why APL Is Still Cool

#12

Post by T_S_ »

bwanab wrote: post #11
T_S_ wrote: post #8

To me the biggest lesson from APL is to always try to manipulate the largest data structure you can your hands on. For example, don't think about for-loops, think about 'map'. When you can do that, life is good. The limitations of the language that I saw (in the mid 90s) were around interoperability. Devs saw it as esoteric and steered toward something more 'marketable' like C++ and later Java. The extensive use of m…

It was used heavily in the fixed income division. I was there during the phase out and among the A-Plus developers there was an "...out of my cold, dead hands" mentality. They (and there were a lot of them) really loved it.

Very true. And a few remaining A+ devs ended up with high job security since there were some systems they were very slow to redo and they were afraid something might break.

Re: Why APL Is Still Cool

#13

Post by evincarofautumn »

It’s certainly a cool language, but this presentation doesn’t really convey it very well. When you want to show me how a language is useful, I absolutely want to hear the boring details, examples of how to manipulate census data, how to serve a web page, and all that. But when you want to show me how a language is cool, I really just want to see gimmicks: neat tricks you can do with the array operations, ways of composing things that are easy in APL that wouldn’t even occur to you in another language, that sort of thing.

I actually got the impression, from the way that Morten put it, that APL is not a terribly good environment for collaboration. It seems best suited to a single person having a “conversation”, if you will, with the APL environment—not necessarily with other developers. I’ve never written anything in APL, let alone in a team, so I could be way off. But then again, if it’s so productive, I’m not sure how much it actually matters if only one guy is working on the software at a time.

Maybe software is only built collaboratively because the tools aren’t powerful enough to let a single developer manage all the complexity. If you have better tools, perhaps you simply don’t need to work in a team.

Re: Why APL Is Still Cool

#14

Post by sethish »

robomartin wrote: post #6

I learned APL in college and used it professionally for about eight years. I really enjoyed the language. Once you know it well enough it creates a very interesting flow condition. You are able to focus on the problem rather than the mechanics of solving it. It's hard to describe but you definitely feel the difference when going from APL to something like C, Forth or Lisp. One of the huge problems with APL back then…

What about J? J was developed Ken Iverson (the creator of APL) as a successor to APL that replaced unicode characters with two character equivalents. It's not greatly publicized, but the latest J was released under the GPLv3 (http://www.jsoftware.com/source.htm).

Re: Why APL Is Still Cool

#15

Post by CUR10US »

robomartin wrote: post #6

I learned APL in college and used it professionally for about eight years. I really enjoyed the language. Once you know it well enough it creates a very interesting flow condition. You are able to focus on the problem rather than the mechanics of solving it. It's hard to describe but you definitely feel the difference when going from APL to something like C, Forth or Lisp. One of the huge problems with APL back then…

kona

I use it as my shell.

Re: Why APL Is Still Cool

#16

Post by oddthink »

T_S_ wrote: post #12
bwanab wrote: post #11

Earlier quoted context omitted.

It was used heavily in the fixed income division. I was there during the phase out and among the A-Plus developers there was an "...out of my cold, dead hands" mentality. They (and there were a lot of them) really loved it.

Very true. And a few remaining A+ devs ended up with high job security since there were some systems they were very slow to redo and they were afraid something might break.

I was stuck debugging a C++ application that was just using A+ objects as its wire protocol. I never even managed to get the fonts to display properly. It was horrible. I ended up having to write my own print-these-boxed-values routines, just to see what was going on.

A few years later, and we were using kdb+ and q to develop major analytics. That was actually a lot of fun.

Re: Why APL Is Still Cool

#17

Post by sunkencity »

I recently bought "APL an interactive approach" and read it. It seems that most of the good stuff from APL is already present in modern languages, and better when it's lazy. The OO stuff in APL looks kind of crufty. Still it's a wonderful fascinating language. In the age of mature open-source it feels very old fashioned with the expensiveness of a decent implementation. Btw, this is a fantastic tv segment from days of yore "The Origins of APL - 1974": http://www.youtube.com/watch?v=8kUQWuK1L4w

Re: Why APL Is Still Cool

#18

Post by silentbicycle »

CUR10US wrote: post #15
robomartin wrote: post #6

I learned APL in college and used it professionally for about eight years. I really enjoyed the language. Once you know it well enough it creates a very interesting flow condition. You are able to focus on the problem rather than the mechanics of solving it. It's hard to describe but you definitely feel the difference when going from APL to something like C, Forth or Lisp. One of the huge problems with APL back then…

kona I use it as my shell.

By which they mean Kona (https://github.com/kevinlawler/kona), an open-source implementation of a K-like language.

Any commands in its repl that are prefixed with "\ " are sent as-is to system(3).

Re: Why APL Is Still Cool

#19

Post by robomartin »

T_S_ wrote: post #7
robomartin wrote: post #6

I learned APL in college and used it professionally for about eight years. I really enjoyed the language. Once you know it well enough it creates a very interesting flow condition. You are able to focus on the problem rather than the mechanics of solving it. It's hard to describe but you definitely feel the difference when going from APL to something like C, Forth or Lisp. One of the huge problems with APL back then…

Morgan Stanley used a variant of APL called A+. It was used quite extensively in parts of the firm. They open-sourced it a while back. http://www.aplusdev.org/

Probably a great internal tool at Morgan Stanley. I haven't heard of anyone outside of them using it seriously, but I could be wrong.

Re: Why APL Is Still Cool

#20

Post by silentbicycle »

ianbishop wrote: post #2

I've always found APL really intriguing. A professor of mine told me about how one of his students used to be able to solve ACM competition problems incredibly fast by simply not having to type very much. There are some insane videos on youtube of people solving problems in APL [1]. But, you know - it's write once, read.. never again. [1] http://www.youtube.com/watch?v=a9xAKttWgP4

It's not that hard to read, it's just dense.

I can read k, which is similarly dense, but limited to ASCII. You may need to read it a bit more slowly, like math, but it is readable. (I can't read Thai, either, but that doesn't make it unreadable.)

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