Really? It doesn't work for me with lexicals
My bad!
The output I showed was genuine, but all conducted in a single run of the debugger.
Which explains it, (though it doesn't exactly satisfy the concept of least surprise), as the globals also existed despite that I had created similarly named lexicals. Which, (apparently naively), I expected to override the globals at the local scope.
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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Symbolic references always refer to globals/package variables, which makes some sense when you know that packages are hashes keyed by the variable names, but lexicals are turned into indexes and the names can be more or less "optimized away" completely.
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Which explains it, (though it doesn't exactly satisfy the concept of least surprise), as the globals also existed despite that I had created similarly named lexicals. Which, (apparently naively), I expected to override the globals at the local scope.
I think that it's important to note that lexicals do override globals—more generally (and more precisely), that the variable declared later overrides the one declared earlier—unless you explicitly ask for globals. Of course, no one would expect $::foo to access a lexical. Similarly, since ${'foo'} requires us to look up a variable by name, rather than location, and since the only way to find variables by name is in the symbol table, we can't possibly 1 get a lexical this way.
(I know that you know this, but I worry about casual future readers thinking that you're suggesting that globals always override lexicals.)
1 As almut correctly points out below, “can't possibly” is almost never correct about Perl. I probably ought to have said “shouldn't”.
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[d/l]
[select] |
#!/usr/bin/perl
use strict;
use warnings;
use PadWalker;
my $foo="foo";
my $bar="f";
my $p = PadWalker::peek_my(0);
print ${$p->{'$'.$bar.'oo'}}, "\n"; # "foo"
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[d/l] |
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