Re^4: chopping a string into slices - is there a more elegant way to do it?

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Re^5: chopping a string into slices - is there a more elegant way to do it? by ikegami (Patriarch) on Nov 04, 2008 at 17:33 UTC
It's not in that one case either. Except when empty, parens never do more than control precedence. Except when empty, they never create a list context. It's almost always used with lists because "`,`" has very low precedence, but it's the commas that create the list, not the parens.	[reply] [d/l]
Re^6: chopping a string into slices - is there a more elegant way to do it? by LanX (Saint) on Nov 04, 2008 at 17:41 UTC
thanx, actually I knew this once ... : ( But in my example they do no harm, just emphasizing the right-to-left priority auf the evaluation. My explanation anyway was wrong! Anyway: I'm a great fan of the syntactical cleansing in Perl 6 and longing to use it ASAP, with or without parrot! UPDATE: You know, sometimes Perl-syntax is like "fizzbin" - the card game Kirk invents on the Mob planet	[reply]
Re^6: chopping a string into slices - is there a more elegant way to do it? by LanX (Saint) on Nov 30, 2008 at 11:17 UTC
> Except when empty, parens never do more than control precedence. Except when empty, they never create a list context. And what about `($a)=@_;` ??? Unfortunately, it's not that easy! Cheers Rolf PS: Just Another example of perl-Fizzbin! ; )	[reply] [d/l]
Re^7: chopping a string into slices - is there a more elegant way to do it? by gone2015 (Deacon) on Nov 30, 2008 at 13:22 UTC
I'm sure I read somewhere that this form can be best understood in terms of the implied or transparent comma -- from memory, that would be a Unicode "ZERO WIDTH NO-BREAK COMMA". (Known to some as the fairy or pixie comma, spreading a little List Context magic while remaining tantalizingly just out of sight. I believe that in Ireland this is also known as one of the extensive family of O'Mission leprechauns.)	[reply]
Re^7: chopping a string into slices - is there a more elegant way to do it? by ikegami (Patriarch) on Nov 30, 2008 at 15:37 UTC
To correct myself, there are very special situations where parens affect the result. `eof` vs `eof()` and `(...)x...` vs `...x...`, for example. And of course `($x)=...` vs `$x=...`. But while parens sometimes do more than control precedence, I can't think of anywhere where non-empty parens create a list context. The parens in `($a)=@_` don't affect context. They cause a list assignment operator (`aassign`) to be used instead of a scalar assignment operator (`sassign`). That said, it's very convenient to think that some parens create a list, even when it isn't technically true. But the code being discussed definitely does not contain parens which could be thought of as "list forming".	[reply] [d/l] [select]
Re^8: chopping a string into slices - is there a more elegant way to do it? by gone2015 (Deacon) on Dec 01, 2008 at 22:44 UTC
Re^9: chopping a string into slices - is there a more elegant way to do it? by ikegami (Patriarch) on Dec 02, 2008 at 05:29 UTC
Re^8: chopping a string into slices - is there a more elegant way to do it? by LanX (Saint) on Nov 30, 2008 at 17:28 UTC
Re^9: chopping a string into slices - is there a more elegant way to do it? by ikegami (Patriarch) on Nov 30, 2008 at 19:01 UTC
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Re^5: chopping a string into slices - is there a more elegant way to do it? by LanX (Saint) on Nov 04, 2008 at 17:28 UTC
I apologize, you were right! `$a= ( test() ); print $a; #> 9 sub test { return (1,2) if wantarray; return 9; }` [download] the paranthesis don't force list context, they seem to be interpreted for the precedence of the lexer!	[reply] [d/l]