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Practical Emacs Lisp

ergoemacs.org

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Re: Practical Emacs Lisp

#11

Post by agumonkey »

PuercoPop wrote: post #7
kazinator wrote: post #5

Earlier quoted context omitted.

I'm an experienced Lisp programmer and most of it looks fine to me from a random sampling, as far as formatting goes. Sometimes a closing parenthesis is on a line by itself: (defun foo () ... ) (let ((x y) (z w) ) ...) Historically, it's not been unheard of that Lisp experts (even implementors) do this sort of thing. Exhibit A, randomly picked source file inside CLISP: http://sourceforge.net/p/clisp/clisp/ci/default/…

I perused a couple of links. This code [0] is pretty much unidiomatic. Closing parens one per line and using setq all over the place. [0]: http://ergoemacs.org/emacs/elisp_grep_string_inside_tag.html

Using lisp to while/set... sigh. This is old age emacs lisp. We need more dash.el. Unfortunately we'd need a more stream/functional buffer API ? I was thinking of porting scheme regexp SRFI because it felt a better fit than re-search-*.

Re: Practical Emacs Lisp

#12

Post by iak8god »

dfan wrote: post #4

Inexperienced Emacs Lisp programmers coming to this site for the first time should be aware that Xah Lee's code is generally not very idiomatic. He discusses it himself here: http://ergoemacs.org/misc/emacs_lisp_coding_style_language_i...

Can you recommend a tutorial that uses idiomatic Emacs Lisp and covers both "why" and "how" of Emacs Lisp at a level appropriate for someone who's used CL and Emacs a lot but has never noticed that he needs ELisp?

Re: Practical Emacs Lisp

#13

Post by PuercoPop »

kazinator wrote: post #9
PuercoPop wrote: post #7

Earlier quoted context omitted.

I perused a couple of links. This code [0] is pretty much unidiomatic. Closing parens one per line and using setq all over the place. [0]: http://ergoemacs.org/emacs/elisp_grep_string_inside_tag.html

That is pretty atrocious. All the initializing setq's could just be init forms in the let. Now you might think that this is also unidiomatic: (setq totalCnt (1+ totalCnt)) Turns out, though, that Elisp doesn't have modify macros, except in the CL compatibility package. What Xah is doing is the same as the accepted SO answer for incrementing a local variable: http://stackoverflow.com/questions/6858894/how-to-increment…

First I forgot to add I Xah Lee's ergo emacs was a valuable resource when learning Emacs. AFAIR it succintly explained emacs base abstractions.

On the setq, I what I meant was iterating through setqs and while (and I seem to recall even catch/throw) as agumonkey mentioned.

Then again, 'in my mind', idiomatic elisp uses cl-lib :D. so (cl-incf total-count) would be better. snakeCase is unidiomatic as well.

Re: Practical Emacs Lisp

#14

Post by PuercoPop »

agumonkey wrote: post #11
PuercoPop wrote: post #7

Earlier quoted context omitted.

I perused a couple of links. This code [0] is pretty much unidiomatic. Closing parens one per line and using setq all over the place. [0]: http://ergoemacs.org/emacs/elisp_grep_string_inside_tag.html

Using lisp to while/set... sigh . This is old age emacs lisp. We need more dash.el. Unfortunately we'd need a more stream/functional buffer API ? I was thinking of porting scheme regexp SRFI because it felt a better fit than re-search-*.

As far as dash.el goes, I find lispm's critique of dash.el pretty convincing[0]. However a more profilic emacs coder fried of mine is undeterred and keeps using modern emacs lisp. I think much of the community does as well.

[0]: https://www.reddit.com/r/lisp/comments/29ufoc/it_is_not_hard...

About Scheme's regexp SRFI, have you seen rx.el? Not quite but I like it myself.

Re: Practical Emacs Lisp

#15

Post by lispm »

Xah Lee can't program a line of Lisp on his own. Most of that code is collected from elsewhere.

There are much better resources to learn Emacs Lisp from.

Re: Practical Emacs Lisp

#18

Post by blue1 »

iak8god wrote: post #12
dfan wrote: post #4

Inexperienced Emacs Lisp programmers coming to this site for the first time should be aware that Xah Lee's code is generally not very idiomatic. He discusses it himself here: http://ergoemacs.org/misc/emacs_lisp_coding_style_language_i...

Can you recommend a tutorial that uses idiomatic Emacs Lisp and covers both "why" and "how" of Emacs Lisp at a level appropriate for someone who's used CL and Emacs a lot but has never noticed that he needs ELisp?

I've also used CL and Emacs a lot; only very recently I've read both GNU Emacs Lisp manuals (introduction and reference). I think as a CL user in a couple of hours you can get an idea of what you can do, and more or less how.

Re: Practical Emacs Lisp

#19

Post by _19qg »

packetslave wrote: post #17
lispm wrote: post #15

Xah Lee can't program a line of Lisp on his own. Most of that code is collected from elsewhere. There are much better resources to learn Emacs Lisp from.

seems like an unnecessary personal attack

It's just the truth. I've seen him posting code for a long time.

He has posted lots of bad advice, because he does not understand much Lisp programming and makes claims about all kinds of random stuff.

Re: Practical Emacs Lisp

#20

Post by agumonkey »

PuercoPop wrote: post #14
agumonkey wrote: post #11

Earlier quoted context omitted.

Using lisp to while/set... sigh . This is old age emacs lisp. We need more dash.el. Unfortunately we'd need a more stream/functional buffer API ? I was thinking of porting scheme regexp SRFI because it felt a better fit than re-search-*.

As far as dash.el goes, I find lispm's critique of dash.el pretty convincing[0]. However a more profilic emacs coder fried of mine is undeterred and keeps using modern emacs lisp. I think much of the community does as well. [0]: https://www.reddit.com/r/lisp/comments/29ufoc/it_is_not_hard... About Scheme's regexp SRFI, have you seen rx.el? Not quite but I like it myself.

IIUC rx.el is a sexp dsl/interface to build vanilla regex down the line right ? from what I remember about scheme SRFI is not the 'syntax' but the return values, you get streams of match, then you can leverage, folds and maps.

lispm point is nice (and no one can argue about evaluation order and count), but beside the battle-tested aspect, `loop` scares the crap out of me. That's even more a reason to prefer things that avoids it in my mind, mentally small building blocks and patterns versus huge macro-based sublanguages. Yes general and probably super-efficiently implemented, but .. nah.

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