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in reply to trouble taking reference of function

Perl's builtins aren't generally made available as subs you can take a reference to. This works though: 

  my $foo = sub { sin(@_) };
  print $foo->(0.5), "\n";

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-sam

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Re^2: trouble taking reference of function
by ikegami (Patriarch) on Mar 03, 2009 at 21:25 UTC
    Beware of prototypes when dealing with functions and named operators. 
    $ perl -wle'print sin(0.5) == sub { sin(@_)    }->(0.5) ?1:0'
0

$ perl -wle'print sin(0.5) == sub { sin($_[0]) }->(0.5) ?1:0'
1

    [download]

    Update: Added code.

[reply]
[d/l]

      Huh? Why does that happen?

      And you didn't even know bears could type.

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[d/l]

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