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Re: computed symbol references

by dragonchild (Archbishop)
on Jul 13, 2004 at 13:21 UTC ( #373969=note: print w/replies, xml ) Need Help??


in reply to computed symbolic references

Your first question is easy to answer.
package x; VERSION = 'bar'; package Foo; VERSION = '1.01'; package main; $bar = '0.01'; $x = 'Foo'; print ${"$x::VERSION"}, $/; print ${$x . "::VERSION"}, $/; ---- 0.01 1.01

The first goes and gets the thing in $x::VERSION (the $VERSION variable in the x:: namespace), then dereferences it as a symbolic reference in the main:: namespace. The second takes the $x variable in the main:: namespace and uses it to create a variable name that is used as a symbolic reference. In this case, the variable $Foo::VERSION.

I'm not sure on the other questions, but you don't have a comma or semi-colon after the ${ ... }. Maybe that's changing your results?

------
We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested

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[Eily]: Discipulus what's the merchandise? Other bi-people?
[1nickt]: marto would like to hear that. Of course he speaks very deliberately and dramatically, allowing pauses between words, so if anybody could pull it off it would be him, or someone impersonating him ...
[Eily]: Discipulus that's a chess joke BTW right? Because bishops don't walk straight :D
[choroba]: stop making chessy jokes about bishops!
[choroba]: I mean cheesy
[LanX]: lol
[ambrus]: no, the chess bishop itself is a joke on real bi-shops
[ambrus]: or at least on the stereotype of bi-shops
[choroba]: we call chess bishops "archers"
[Eily]: choroba sorry, I had to get that off my chess

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