Re^2: If condition failing..

1.What is the use of undef here?

$pathname_versions{$1}{$2} = undef;
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2.How do I do a hash look up for the hash pathname_versions to see if $2(version in the second list) is less than the version in the list 1?

Comment on Re^2: If condition failing.. Download Code

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Re^3: If condition failing.. by Anonyrnous Monk (Hermit) on Dec 13, 2010 at 01:08 UTC
I didn't follow the discussion in the original thread, so maybe I'm missing something... but why don't you store the version as the value of the hash entries? `while (<IN>) { # first list next unless ( m:(.+?)#(\d+)$: ); $pathname_versions{$1} = $2; }` [download] In this case you could later simply do (where `$pathname_versions{$1}` retrieves the corresponding version from the first list) `while (<IN>) { # second list next unless ( m:(.+?)#(\d+)$: ); ... if ( $pathname_versions{$1} < $2 ) { ...` [download]	[reply] [d/l] [select]
Re^4: If condition failing.. by perl_mystery (Beadle) on Dec 13, 2010 at 01:49 UTC
Actually I want the other way like below,but if i use it i am getting the below error. `if ( $pathname_versions{$1} > $2) { #if the version in list2 i +s less than version for the same path in list1 print "IN\n"; }` [download] Can't use string ("6") as a HASH ref while "strict refs" in use at orphan_overwrite.pl line 30, <IN> line 28	[reply] [d/l]
Re^5: If condition failing.. by Anonyrnous Monk (Hermit) on Dec 13, 2010 at 02:08 UTC
`Can't use string ("6") as a HASH ref` This is probably because somewhere else you still have `$pathname_versions{$1}{$2}`. So, if `$pathname_versions{$1}` is now "6", for example, the `{$2}` would be trying to dereference the value "6", i.e. `"6"->{$2}`, which doesn't make much sense...	[reply] [d/l] [select]