Usage patterns strike back

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Re: Usage patterns strike back by chip (Curate) on Mar 19, 2004 at 17:56 UTC
Interestingly, unary minus could default to string or numeric behavior and the trap would still bite. -- Chip Salzenberg, Free-Floating Agent of Chaos	[reply]
Re: Usage patterns strike back by halley (Prior) on Mar 19, 2004 at 18:09 UTC
The difference is the magical parsing of `while (<HANDLE>)`. Try with `B::Deparse`: `while (defined($_ = <DATA>)) { last; }` [download] -but- `while (-<DATA>) { print $_; }` [download] The second form doesn't actually assign the line into any variable. (Of course, a negative "Just" is still not negative.) -- `[ e d @ h a l l e y . c c ]`	[reply] [d/l] [select]
Re: Usage patterns strike back by theguvnor (Chaplain) on Mar 18, 2004 at 21:38 UTC
Explanation please? I'd like to avoid the trap but I'm not savvy enough to quite take your meaning. [Jon]	[reply]
Re: Re: Usage patterns strike back by kappa (Chaplain) on Mar 19, 2004 at 12:59 UTC
You can run it. Then remove that '-' and run again. Compare results. Hm, work it out for yourself, you'll get much more satisfaction, really :)	[reply]
Re: Usage patterns strike back by muba (Priest) on Mar 20, 2004 at 10:30 UTC
Ok, I do understand what's happening, but I don't understand why somebody would want to read data from a HANDLE and then get a negative value of it? My first thought was that -<HANDLE> would maybe read from the last line of the file towards the first line, but that does not seem to be the case. So, what's the trap? Who wants to do this? And what is their target?	[reply]
Re: Re: Usage patterns strike back by kappa (Chaplain) on Mar 22, 2004 at 09:16 UTC
Oh, that's just a short and 'obfu' way of turning `<HANDLE>` into an expression involving `<HANDLE>` for the sake of this very example.	[reply] [d/l] [select]