in reply to looking for a good idiom: return this if this is true

I have no better idea than the other monks so far, but I wonder how 
eval { return thatroutine() || die };

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is supposed to work, since the return does not return from the sub surounding the eval.
Boris

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Re^2: looking for a good idiom: return this if this is true
by Zaxo (Archbishop) on Mar 05, 2005 at 18:38 UTC

    The || operator is the high priority logical or, so if thatroutine() evaluates false, die is evaluated before return is.

    Update: Oops, I misunderstood your objection, which is correct: 

    $ perl -Mstrict -we'sub bar {"baz"} sub foo {eval{return bar() || die}
+; "quux"} print foo()'
quux$

    [download]
    If the eval return was effective in the foo() call, should have printed "baz".

    After Compline,
    Zaxo

[reply]
[d/l]
      Thats clear to me, but I do not understand the other part: The question is how to return a value, if it is true and continue otherwise. 
      sub that { 5 }
sub xx{ eval { return that() || die }; 1 }
print xx;
__OUTPUT__
1

      [download]
      But the op wants 5 and that the part outside the eval is not executed expect when that is false.
      Boris
[reply]
[d/l]

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