How do I...Conditional hash value

S_Shrum has asked for the wisdom of the Perl Monks concerning the following question:

OK...more of a 'Is it possible to do this' sorta question:

my %required = (
    path => if ( $env{'HTTP_HOST'} = 'www.shrum.net' ) { "g:/websites/
+shrum.net/" || "d:/users/http/html/"; },
);
[download]

I know that the above won't work but you get the idea.

Is it possible to set up a conditional eval like this or do I need to do this outside the hash declaration?

On the other hand...is there a better way of dealing with pathnames...my code originally was written for Apache but IIS doesn't use environment variables like DOCUMENT_ROOT and so forth.

TIA

======================
Sean Shrum
http://www.shrum.net

Comment on How do I...Conditional hash value Download Code

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Re: How do I...Conditional hash value by myocom (Deacon) on Jul 26, 2002 at 22:20 UTC
First off, beware the "= vs. eq vs. ==" bug. Remember that = does an assignment, == compares numeric values, and eq compares string values. Having said that, what you're probably looking for is the ternary ?: operator (documented in perlop). I'd write what you're looking for like this: `my %required; $required{path} = ($ENV{HTTP_HOST} eq 'www.shrum.net') ? 'g:/websites/shrum.net/' : 'd:/users/http/html/';` [download] Then again, if you have several keys to set, you're probably better off doing: `my %required; if ($ENV{HTTP_HOST} eq 'www.shrum.net') { # We now know which # platform we're on... $required{path} = 'g:/websites/shrum.net/'; $required{someotherkey} = 'some other string'; } else { $required{path} = 'd:/users/http/html/'; $required{someotherkey} = 'some different string'; }` [download] "One word of warning: if you meet a bunch of Perl programmers on the bus or something, don't look them in the eye. They've been known to try to convert the young into Perl monks." - Frank Willison	[reply] [d/l] [select]
Re: How do I...Conditional hash value by dws (Chancellor) on Jul 26, 2002 at 22:09 UTC
Would this work? `my %required = ( path => ($ENV{'HTTP_HOST'} eq "www.shrum.net") ? "g:/websites/shrum.net/" : "d:/users/http/html/" );` [download]	[reply] [d/l]
Re^2: How do I...Conditional hash value by Anonymous Monk on Oct 05, 2015 at 21:13 UTC
Yes that should work... Also see: `use Data::Dumper; my $i1 =1; my %hash = (k1 => {k2 => ($i1 ? 'this' : 'that') }); print Dumper(\%hash) . "\n"; # this $i1 = 0; %hash = (k1 => {k2 => ($i1 ? 'this' : 'that') }); print Dumper(\%hash) . "\n"; # that` [download] --Div	[reply] [d/l]