Re: SEXP?
Alexander Burger a...@software-lab.de writes: Hi Alex, I wonder if there is a way in PicoLisp to check if some function argument is a SEXP, i.e. if something like a function 'sexp? exists that returns T if the argument is a SEXP. I'm a bit puzzled by this question. To my understanding, every possible expression in PicoLisp is a SEXP. Even auto-quoting expressions like I'm puzzled too ... : T - T : abc - abc : (1 2 3) - (1 2 3) are SEXPs (though it might be argued that the last one is not, since it doesn't contain any symbols). .. and was a bit confused when asking, I probably meant 'list' instead of SEXP. e.g., when I filter function args that are given as unevaluated list, and should be either names of existing files or Emacs Lisp expressions: ,--- | (filter 'info CmdLineArgs) `--- ,--- | (filter '((X) (not (info X))) CmdLineArgs) `--- then invalid file names fall into category 'elisp expressions' and cause errors later on. But its probably better to check the expressions of the elisp side and this question is kind of obsolete, but thanks anyway. With so many occurences fo SEX in this post, I wonder if it will be filtered as SPAM or actually posted in the mailing list Worked :) And NSA will only read read (and not filter) it. at least I sent it only once and are not classified as spammer now, hopefully ;) -- cheers, Thorsten -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: SEXP?
Hi Thorsten, I'm a bit puzzled by this question. To my understanding, every possible expression in PicoLisp is a SEXP. Even auto-quoting expressions like ... .. and was a bit confused when asking, I probably meant 'list' instead of SEXP. ... then invalid file names fall into category 'elisp expressions' and cause errors later on. But its probably better to check the expressions of the elisp side and this question is kind of obsolete, but thanks anyway. In general, there is no way to detect statically whether an s-expression is executable or not. Something like (a b c d) may not be executable *now*, because 'a' is not a function, but it may be shortly after. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: SEXP?
On Monday 01 of July 2013 07:39:49 you wrote: Hi Thorsten, I wonder if there is a way in PicoLisp to check if some function argument is a SEXP, i.e. if something like a function 'sexp? exists that returns T if the argument is a SEXP. how about (pair 'any) ? basically the opposite of (atom 'any) -- dexen deVries [[[↓][→]]] Take care of the luxuries and the necessities will take care of themselves. -- L. Long -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: SEXP?
dexen deVries dexen.devr...@gmail.com writes: On Monday 01 of July 2013 07:39:49 you wrote: Hi Thorsten, I wonder if there is a way in PicoLisp to check if some function argument is a SEXP, i.e. if something like a function 'sexp? exists that returns T if the argument is a SEXP. how about (pair 'any) ? basically the opposite of (atom 'any) thats probably what I was looking for, thanks, besides the fact that Alex is of course right about the difficulties with doing these kind of tests in a dynamic environment. -- cheers, Thorsten -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: SEXP?
Hi Thorsten, I've used fun? to determine if an argument had the proper form of something that was executable or if it was data. It may not work in all cases, but it was sufficient for my use case. As Alex mentioned, it won't let you know whether it's actually executable or not. I think of it as having the potential to be executable. Joe On Mon, Jul 1, 2013 at 4:50 AM, Thorsten Jolitz tjol...@gmail.com wrote: dexen deVries dexen.devr...@gmail.com writes: On Monday 01 of July 2013 07:39:49 you wrote: Hi Thorsten, I wonder if there is a way in PicoLisp to check if some function argument is a SEXP, i.e. if something like a function 'sexp? exists that returns T if the argument is a SEXP. how about (pair 'any) ? basically the opposite of (atom 'any) thats probably what I was looking for, thanks, besides the fact that Alex is of course right about the difficulties with doing these kind of tests in a dynamic environment. -- cheers, Thorsten -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: SEXP?
Joe Bogner joebog...@gmail.com writes: Hi Joe, I've used fun? to determine if an argument had the proper form of something that was executable or if it was data. It may not work in all cases, but it was sufficient for my use case. As Alex mentioned, it won't let you know whether it's actually executable or not. I think of it as having the potential to be executable. 'fun? would be another possibility, but 'pair is a little bit more tolerant (returns non-NIL in more cases), and since I apply it on Emacs Lisp (and not PicoLisp) expressions, this tolerance seems to be a good thing. But thanks for the tip anyway! On Mon, Jul 1, 2013 at 4:50 AM, Thorsten Jolitz tjol...@gmail.com wrote: dexen deVries dexen.devr...@gmail.com writes: On Monday 01 of July 2013 07:39:49 you wrote: Hi Thorsten, I wonder if there is a way in PicoLisp to check if some function argument is a SEXP, i.e. if something like a function 'sexp? exists that returns T if the argument is a SEXP. how about (pair 'any) ? basically the opposite of (atom 'any) thats probably what I was looking for, thanks, besides the fact that Alex is of course right about the difficulties with doing these kind of tests in a dynamic environment. -- cheers, Thorsten -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe -- cheers, Thorsten -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
