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

[download]

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

In reply to Re: computed symbol references by dragonchild
in thread computed symbolic references by valentin

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