Re^4: Accessing lexicals in other scopes dynamically by name

>Call the sub from outside the scope in which $x resides and you'll see it fail.

please define your understanding of "capture" and "scope" (dynamic or static).

Cheers Rolf

Comment on Re^4: Accessing lexicals in other scopes dynamically by name

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Re^5: Accessing lexicals in other scopes dynamically by name by ikegami (Patriarch) on Jul 30, 2010 at 18:09 UTC
Capturing preserves a variable beyond the end of its normal scope. `sub make_closure { my ($x) = @_; return sub { $x }; } my $c1 = make_closure("a"); my $c2 = make_closure("b"); say $c1->(); # a say $c2->(); # b` [download] The $x from the first call to make_closure and the $x from the second call to make_closure are kept alive beyond the end of their normal scope (the end of that call to make_closure).	[reply] [d/l]

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Re^5: Accessing lexicals in other scopes dynamically by name
by ikegami (Patriarch) on Jul 30, 2010 at 18:09 UTC

sub make_closure {
   my ($x) = @_;
   return sub { $x };
}

my $c1 = make_closure("a");
my $c2 = make_closure("b");

say $c1->();  # a
say $c2->();  # b
[download]

The $x from the first call to make_closure and the $x from the second call to make_closure are kept alive beyond the end of their normal scope (the end of that call to make_closure).

[reply]
[d/l]