Are the references to anonymous code blocks in Perl always constant, because they are fixed at compile time?

No and no; its just another variable. consider 

$ perl -le " for(1..3){ my$f=$_; print\$f; }"
SCALAR(0x99b824)
SCALAR(0x99b824)
SCALAR(0x99b824)

[download]

versus 

$ perl -le " sub ff { my $f = $_; return \$f } print ff() for 1..3;"
SCALAR(0x3f9bcc)
SCALAR(0x3f9bbc)
SCALAR(0x3f9bcc)

[download]

What perl does, how perl optimizes, how perl reuses allocated memory, depends on what the code does

In reply to Re: References for ano subs fixed at compile time? (no) by Anonymous Monk
in thread References for ano subs fixed at compile time? by LanX

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