in reply to Eval str return different from Eval block return

You have a precedence/grouping problem:

print "Eval ret:",readonly((eval'capture(5)')->[0]);

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and
print "Eval ret:",readonly(eval('capture(5)')->[0]);

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both print "Str Eval ret   :1"

Update: Now that is odd that the grouping doesn't work for you,, mine's on Linux/Perl5.6.1.

Update 2 : Sure does look like a platform difference, and where one should not be. I can confirm that demerphq's initial results agree with what mine does with that code. It appears that it's only the parenthesized ones that differ.

Update 3 : One more test case:

print "Eval ret:",readonly(eval('capture(5)'->[0]));

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prints "Str Eval ret   :0" on mine. It looks like AS groups thataway. Curiouser and curiouser.

After Compline,
Zaxo

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Re: Re: Eval str return different from Eval block return
by Dog and Pony (Priest) on May 17, 2002 at 09:49 UTC
    Not on Win2k / ActivePerl 5.6.1 they don't. So this could be a platform issue then? 
    No eval        :1
In str eval    :1
In block eval  :1
Block Eval ret :1
Str Eval ret   :0
Str Eval ret2  :0

    [download]
    Update:

    On the same machine, with cygwin and perl 5.6.1, it runs fine: 

    No eval        :1
In str eval    :1
In block eval  :1
Block Eval ret :1
Str Eval ret   :1
Str Eval ret2  :1

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    You have moved into a dark place.
    It is pitch black. You are likely to be eaten by a grue.
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[d/l]
[select]
Re: Re: Eval str return different from Eval block return
by demerphq (Chancellor) on May 17, 2002 at 09:47 UTC
    Which OS and Perl version Zaxo? I still get incorrect results 
    use strict;
use warnings;
sub capture {\@_};
sub readonly{ my $v=$_[0]; eval{$_[0]=$v;1} ? 0 : 1 }

$\="\n";
print "No eval        :",readonly(capture(5)->[0]);
eval '
print "In str eval    :",readonly(capture(5)->[0]);
';
eval {
print "In block eval  :",readonly(capture(5)->[0]);
};
print "Block Eval ret :",readonly(eval{capture(5)}->[0]);
print "Str Eval ret   :",readonly((eval'capture(5)')->[0]);
print "Str Eval ret2  :",readonly(eval('capture(5)')->[0]);
__END__
No eval        :1
In str eval    :1
In block eval  :1
Block Eval ret :1
Str Eval ret   :0
Str Eval ret2  :0

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    Yves / DeMerphq
    ---
    Writing a good benchmark isnt as easy as it might look.

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[d/l]

      On Win NT and AS perl 5.6.1 you get

      --<br>
No eval        :1
In str eval    :1
In block eval  :1
Block Eval ret :1
Str Eval ret   :0
Str Eval ret2  :0
--

      [download]
      Anthony Staines
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[d/l]

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