Hi Vladimir,
Thanks a lot for doing this work, it'll be seriously great to have implicit return!
On 2009-11-04, at 12:57 PM, Vladimir Sedach wrote:
Hello,
Many of you have been asking for this for a long time, and based on feedback (as well as my own experience) the lack of this feature has been the biggest cause of bugs in PS code, so it's with a bit of joy that I just pushed out a patch to add implicit returns to PS functions (including lambdas and flet/labels) to the repository just now. Please try it out and report any bugs you find!
The first one I encountered was to do with the special return handling for case/switch.
1) The return special form assumes the wrong switch/case structure for these statements, it should be:
(switch-case what &rest clauses)
rather than:
(switch-case what clauses)
...in both the destructing code and the reconstruction of the clauses, having been updated with the return statement.
2) The return special form needs to handle break forms in switch/case; rather than wrapping a break statement, it should remove it and wrap the previous expression in the return statement. Here's the (incorrect) output that I'm getting after having fixed the first issue:
(ps (lambda () (case 1 (0 1) (otherwise 2))))
"function () { switch (1) { case 0: 1; return break; default: return 2; }; };"
I think we want to see:
"function () { switch (1) { case 0: return 1; default: return 2; }; };"
- Scott
I just pushed a patch that should fix that. Thanks for the bug report!
Vladimir
2009/11/4 sblist@me.com:
Hi Vladimir,
Thanks a lot for doing this work, it'll be seriously great to have implicit return!
On 2009-11-04, at 12:57 PM, Vladimir Sedach wrote:
Hello,
Many of you have been asking for this for a long time, and based on feedback (as well as my own experience) the lack of this feature has been the biggest cause of bugs in PS code, so it's with a bit of joy that I just pushed out a patch to add implicit returns to PS functions (including lambdas and flet/labels) to the repository just now. Please try it out and report any bugs you find!
The first one I encountered was to do with the special return handling for case/switch.
- The return special form assumes the wrong switch/case
structure for these statements, it should be:
(switch-case what &rest clauses)
rather than:
(switch-case what clauses)
...in both the destructing code and the reconstruction of the clauses, having been updated with the return statement.
- The return special form needs to handle break forms in
switch/case; rather than wrapping a break statement, it should remove it and wrap the previous expression in the return statement. Here's the (incorrect) output that I'm getting after having fixed the first issue:
(ps (lambda () (case 1 (0 1) (otherwise 2))))
"function () { switch (1) { case 0: 1; return break; default: return 2; }; };"
I think we want to see:
"function () { switch (1) { case 0: return 1; default: return 2; }; };"
- Scott
parenscript-devel mailing list parenscript-devel@common-lisp.net http://common-lisp.net/cgi-bin/mailman/listinfo/parenscript-devel
On 2009-11-04, at 10:33 PM, Vladimir Sedach wrote:
I just pushed a patch that should fix that. Thanks for the bug report!
Thanks for the speedy fix!
Another trickiness around SWITCH is the behavior of fall-through cases -- it seems like there's still a bug lurking here:
PS> (ps (lambda () (switch 0 (1 1 break) (2 2 break) (3 (do-something)) (default 4)))) "function () { switch (0) { case 1: return 1; case 2: return 2; case 3: return doSomething(); default: return 4; }; };"
I think that case 3 shouldn't return, since there was no break there originally, so the expected behaviour is to doSomething() and then fall-through for the return value.
- Scott
2009/11/4 sblist@me.com:
Hi Vladimir,
Thanks a lot for doing this work, it'll be seriously great to have implicit return!
On 2009-11-04, at 12:57 PM, Vladimir Sedach wrote:
Hello,
Many of you have been asking for this for a long time, and based on feedback (as well as my own experience) the lack of this feature has been the biggest cause of bugs in PS code, so it's with a bit of joy that I just pushed out a patch to add implicit returns to PS functions (including lambdas and flet/labels) to the repository just now. Please try it out and report any bugs you find!
The first one I encountered was to do with the special return handling for case/switch.
- The return special form assumes the wrong switch/case
structure for these statements, it should be:
(switch-case what &rest clauses)
rather than:
(switch-case what clauses)
...in both the destructing code and the reconstruction of the clauses, having been updated with the return statement.
- The return special form needs to handle break forms in
switch/case; rather than wrapping a break statement, it should remove it and wrap the previous expression in the return statement. Here's the (incorrect) output that I'm getting after having fixed the first issue:
(ps (lambda () (case 1 (0 1) (otherwise 2))))
"function () { switch (1) { case 0: 1; return break; default: return 2; }; };"
I think we want to see:
"function () { switch (1) { case 0: return 1; default: return 2; }; };"
- Scott
parenscript-devel mailing list parenscript-devel@common-lisp.net http://common-lisp.net/cgi-bin/mailman/listinfo/parenscript-devel
parenscript-devel mailing list parenscript-devel@common-lisp.net http://common-lisp.net/cgi-bin/mailman/listinfo/parenscript-devel
Here's another:
PS> (ps (lambda () (case x (a 'eh) (b 'bee)))) => "function () { switch (x) { case a: return 'eh'; case b: return 'bee'; }; };"
... ok, so far so good.
PS> (ps (lambda () (macrolet ((x () 1)) (case (x) (a 'eh) (b 'bee))))) => "function () { return switch (1) { case a: 'eh'; break; case b: 'bee'; }; };"
- Scott
On 2009-11-04, at 10:33 PM, Vladimir Sedach wrote:
I just pushed a patch that should fix that. Thanks for the bug report!
Vladimir
2009/11/4 sblist@me.com:
Hi Vladimir,
Thanks a lot for doing this work, it'll be seriously great to have implicit return!
On 2009-11-04, at 12:57 PM, Vladimir Sedach wrote:
Hello,
Many of you have been asking for this for a long time, and based on feedback (as well as my own experience) the lack of this feature has been the biggest cause of bugs in PS code, so it's with a bit of joy that I just pushed out a patch to add implicit returns to PS functions (including lambdas and flet/labels) to the repository just now. Please try it out and report any bugs you find!
The first one I encountered was to do with the special return handling for case/switch.
- The return special form assumes the wrong switch/case
structure for these statements, it should be:
(switch-case what &rest clauses)
rather than:
(switch-case what clauses)
...in both the destructing code and the reconstruction of the clauses, having been updated with the return statement.
- The return special form needs to handle break forms in
switch/case; rather than wrapping a break statement, it should remove it and wrap the previous expression in the return statement. Here's the (incorrect) output that I'm getting after having fixed the first issue:
(ps (lambda () (case 1 (0 1) (otherwise 2))))
"function () { switch (1) { case 0: 1; return break; default: return 2; }; };"
I think we want to see:
"function () { switch (1) { case 0: return 1; default: return 2; }; };"
- Scott
parenscript-devel mailing list parenscript-devel@common-lisp.net http://common-lisp.net/cgi-bin/mailman/listinfo/parenscript-devel
parenscript-devel mailing list parenscript-devel@common-lisp.net http://common-lisp.net/cgi-bin/mailman/listinfo/parenscript-devel
parenscript-devel@common-lisp.net
-
sblist＠me.com -
Vladimir Sedach