our $VERSION = "0.001"; $VERSION = eval $VERSION;

The thing I don't like about this is that (depending upon the original string), you might find that, after the eval is done, "$VERSION" ne <original_string>
No such problem with "0.001", but consider this simple script: 
use strict;
use warnings;

my $str = "2.30";

our $VERSION = $str;
$VERSION = eval $VERSION;

print "WTF\n" if $VERSION ne $str;

[download]
That outputs "WTF".
That is, having assigned the string "2.30" to $VERSION, the eval forces $VERSION into a state where it stringifies to something other than "2.30" - namely to "2.3".

It's probably of little importance, but I found it annoying enough to immediately replace all occurrences of eval $VERSION in my .pm files with #eval $VERSION
I've no regrets about having done that, yet.

Notably, with the eval removed, we can then perform both numeric and string comparisons reliably: 
use strict;
use warnings;

my $str = "2.30";

our $VERSION = $str;
print "OK 1\n" if $VERSION == 2.3;
print "OK 2\n" if $VERSION == $str;
print "OK 3\n" if $VERSION eq $str;
print $VERSION, " ", $str, "\n";
print "$VERSION $str\n";

__END_
outputs:
OK 1
OK 2
OK 3
2.30 2.30
2.30 2.30

[download]
I find that saner and preferable ... though I now always avoid using version strings that terminate with one or more zeros ... just in case ;-)

Cheers,
Rob

In reply to Re^6: Why eval $version? by syphilis
in thread Why eval $version? by Aldebaran

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