On Mon, Jan 13, 2014 at 8:32 PM, Joe Bogner <joebog...@gmail.com> wrote:
> PicoLisp
>
> (de rdConf (File)
> (pipe (in File (while (echo "#" ";") (till "^J")))
> (while (read)
> (skip)
> (set @ (or (line T) T)) ) ) )
Is that complete?
I learned lisp back in highschool, and I've used drracket and emacs
and other such lisp environments, but never learned picolisp. I tried
to install picolisp but it would not build for me and I do not feel
like debugging the source for picolisp just for this message.
My impression, though, is that a J implementation like what you have
written would look something like this:
conf=: a:-.~(#~ 1 -.&e. '#;'&e.S:0)<;._2 fread file
In other words, read the file as lines, removing blank lines and comment lines.
If all you are doing is saving the unparsed lines then we should
expect simpler code. But maybe I have missed a subtlety of picolisp?
I get that @ is a wild card, but I do not understand the mechanism
well enough to say whether your implementation is correct, nor do I
know whether (while (read) .. is stashing the read result somewhere or
what. Nor do I know if your skip is assuming a rigid file structure or
is allowing free-form comments in the config file.
> If I compare that to the your J implementation
>
>> deb L:0@:(({.~ ; [: < [: ;^:(1=#) ',' cut (}.~>:)) i.&1@:e.&' =')&>@(#~
>> a:&~: > ';#'e.~{.&>)@:(dlb&.>)@:(LF&cut)
>
> This J implementation feels more like code golf or a compressed
> string. How many tokens/operations are included in it? I won't count,
> but I am fairly sure it's more than the (pipe, in, while, echo, till,
> read, skip, set, or, line) 9 in the PicoLisp example.
I count 64 tokens in the J implementation and 54 tokens in your
PicoLisp example. I'm not sure why you have implied that parentheses
are not tokens but I do not think they qualify as whitespace?
We could get further into parsing and punctuation issues, but I'm not
sure whether that would be relevant.
> When reading a long J string or an entry in the obfuscated C code
> contest, I try to recognize patterns or operations. Having used J for
> about 6 months, I can recognize probably about half the operations in
> that string without having to look them up. That's progress. It still
> feels like a "run on sentence" which is harder to read than short
> sentences.
I also usually prefer shorter sentences. Not always, but I'd probably
try to split Dan's code into two or three lines. Posting a fair bit of
code to email has been an influence there.
I imagine I would also favor a shorter implmentation than what Dan has
done here. For example, in his code I see the phrase e.&' =' but I see
no equals signs in the config file nor in the specification on the
companion task (whose J entry should perhaps be simplified?).
> I think there's a fine balance between tacit expressions and clarity.
> It may be my level of inexperience with the language. However, I
> wonder if I've put as much time on it as any intro-level APL
> programmer. Are there any conventions in the language for # of tokens,
> trains, etc for a readable sentence?
Personal taste?
Thanks,
--
Raul
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