> Hello folks, > > I'm wondering if any of you could help me with a code problem? I'm > relatively new to Perl, coming to it from AppleScript, and I've written > a Perl script that parses my server access_log and creates a hash of > hashes that looks essentially like this: > > 192.168.1.1 = > $user_agent = "...GoogleBot..." > $user_type = "robot" > 192.168.1.3 = > $user_agent = "...Linux...Firefox..." > $user_type = "human" > 192.168.1.4 = > $user_agent = "...Yahoo! Slurp..." > $user_type = "robot" > 192.168.1.5 = > $user_agent = "...Windows...MSIE..." > $user_type = "human" > etc... > > So, in the first hash, the ip address is the key and the value is the > second, nested hash. > > I want to traverse that hash of hashes to extract the user agent of > each IP whose user type is "robot" like this: > > LIST OF ROBOTS VISITING SITE: > 192.168.1.1 "...GoogleBot..." > 192.168.1.4 "...Yahoo! Slurp..." > etc... > > I've been struggling with various versions of a foreach loop but can't > seem to get it to work. Is it possible to traverse a hash of hashes and > extract data based on a value from a key/value pair that is nested in > another hash? >
What you are doing would be much clearer if you included actual code. My instincts tell me you might be building your hash-of-hashrefs incorrectly, which case my example here will be of no help to you. Use Data::Dumper to make sure your hash of hashrefs is what you think it is ... ................................... BEGIN PERL CODE .................... #!/usr/bin/perl # File jm.pl use strict; use warnings; my %log= ( '192.168.1.1' => { user_agent => '...GoogleBot...', user_type => 'robot' }, '192.168.1.3' => { user_agent => '...Linux...Firefox...', user_type => 'human' }, '192.168.1.5' => { user_agent => '...Windows...MSIE...', user_type => 'human' } ); foreach my $key (keys %log ) { print "$key \"$log{$key}{user_agent}\"\n"; } .................................... END PERL CODE ..................... Produces the follwoing output: lawrence /tmp > perl ./jm.pl 192.168.1.1 "...GoogleBot..." 192.168.1.3 "...Linux...Firefox..." 192.168.1.5 "...Windows...MSIE..." Another place that could be giving you grief is trying to embed dollar signs in your hash keys - I'm sure it's possible, but it causes much grief and pain and anguish. -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- Lawrence Statton - [EMAIL PROTECTED] s/aba/c/g Computer software consists of only two components: ones and zeros, in roughly equal proportions. All that is required is to sort them into the correct order. -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
