October 2012 - parenscript-devel - mailman3.common-lisp.net

[parenscript-devel] Bug: let within an outer let's init-form
by Andy Peterson 29 Nov '12

29 Nov '12

If you use a let within the init-form of an outer let, the result is invalid javascript code. Here is a simplified example: (ps (let ((x (let ((y (a))) (b) y))) (1+ x))) ==> "(function () { var y; var x = (y = a(), (b(), y)); return x + 1; })();" Not that I would normally write such code, but the inner "let" was generated by a macro. And many macros use "let"* *with gensyms. In my case, the macro used "ps-once-only". Andy Peterson

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[parenscript-devel] suggestion for json printing
by Canhua 29 Nov '12

29 Nov '12

hi, I think it would be nice to read if parenscript compiler pretty-print json object in the output, in particular properly indent it, rather than print it on one line like right now.

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[parenscript-devel] APPLY of method functions
by Boris Smilga 24 Nov '12

24 Nov '12

Hello. I have noticed that the macro APPLY in PS expands to a call to the function's apply method with an invariable “this” as its first argument (thisArg, per http://ecma-international.org/ecma-262/5.1/ #sec-15.3.4.3). When the function is a method of an object, this may result in incorrect code. Consider: (lambda (some-vector start del-count &rest elts) ... (apply (@ some-vector splice) start del-count elts) ... ) => (function (someVector, start, delCount) { var elts = []; for (var i120 = 0; i120 < arguments.length - 3; i120 += 1) { elts[i120] = arguments[i120 + 3]; }; ... someVector.splice.apply(this, [start, delCount].concat(elts)); ... }); Whereas, to be correct, the apply part should go like someVector.splice.apply(someVector, [start, delCount].concat (elts)); Please find attached a patch which makes APPLY recognize property accessors in the function argument, separate them into object and method, and pass the object to the method's apply. For cases which require more fine-grained control, the patch adds an APPLY-TO macro which provides for a completely custom thisArg. There's also a separate patch with a couple of unit tests. Yours, — B. Smilga.

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[parenscript-devel] innerHTML => inner-h-t-m-l?
by Philipp Marek 11 Oct '12

11 Oct '12

Hello everybody, is there a shorter (nicer) way to use "innerHTML" with parenscript? The obvious translation doesn't look that good, so I'm wondering if there's a better way. Regards, Phil

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[parenscript-devel] Symbol conflicts with eg. alexandria and iterate
by Philipp Marek 10 Oct '12

10 Oct '12

Hello, I'm using parenscript from current quicklisp. In the tutorial I see that parenscript should be :USEd. My package already uses :ITERATE and :ALEXANDRIA - and that gives me conflicts for (at least) alexandria:switch and iterate:for. Is there a preferred way to handle this? Should I _not_ use parenscript, but use the PS: prefix? And for what symbols? PS:DEFUN to get a javascript function defined? Or would it be better to make parenscript :USE alexandria and iterate - AFAICS the symbols are unbound anyway (the few that I've looked at), so there should be no problem importing them? Any help is appreciated. Thank you! Regards, Phil

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[parenscript-devel] return in onclick
by Philipp Marek 09 Oct '12

09 Oct '12

Another question: the tutorial has :onclick (ps (previous-image) (return false)) but the reference says RETURN can only be used to return a value from a function and indeed, when trying to use return in a (:a :href "..." :onclick (ps (my-func) (return false))) I get a warning Returning from unknown block nilBlock What's the typical way for PS use in an onclick handler? Thank you for your patience! Regards, Phil

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