searching a hash 1

[ailse]

I have implemented a search of a hash using a keyword as follows:

while ( my ($id, $description) = each(%hash) ) {
	if ($description =~ /$query_string/i) {
   	
	print "$id" . "\t" . "$description";
	print "\n";
	}
}

my problem is to do with returning an error message if $query_string does not appear in the hash. if i modify the code as follows:

while ( my ($id, $description) = each(%hash) ) {
	if ($description =~ /$query_string/i) {
   	
	print "$id" . "\t" . "$description";
	print "\n";
	}
	else {
	print "No matching results!\n";
	}
}

the error message "no matching results" prints for every record in the hash, when i just want it to print once. so if my hash has four records (just as an example, i actually have over 19,000):

id1 description
id2 description
id3 description
id4 description

and $query_string does not appear, the above code is returning:

No matching results!
No matching results!
No matching results!
No matching results!

when it should only return this message once - any ideas how to work around this?

 

[spookie]

Print it outside while loop

my $flag = 0;
while ( my ($id, $description) = each(%hash) ) {
    if ($description =~ /$query_string/i) {
    $flag = 1 ;   
    print "$id" . "\t" . "$description";
    print "\n";
    }
}
if ( $flag == 0 ) {
print "No matching results!\n";
}

--------------------------------------------------------------------------
I never set a goal because u never know whats going to happen tommorow.

 

[PaulTEG]

That seems to be a lot of work ...

can you force your hash to a particular case, eg lower

$qs=lc($query_string);
if (exists($hash($qs)) {
  print "Gotcha"
}

Paul
------------------------------------
Spend an hour a week on CPAN, helps cure all known programming ailments ;-)

 

[ishnid]

Agreed. 19,000 regexp matches for each search just isn't practical. However, it's the values that the OP is searching rather than the keys, so that solution won't work, Paul.

 

[PaulTEG]

gyaargh .... I need a holiday

Paul
------------------------------------
Spend an hour a week on CPAN, helps cure all known programming ailments ;-)

 

[icrf]

heh, jump across the pool for the weekend. Tuesday next week, we celebrate the day we politely asked your countrymen (or was it your neighbors?) to go home.

uhh...can't post without content, so here's another way. I've always liked the list operators.

[COLOR=#0000FF]my[/color] $flag = [COLOR=#FF0000]0[/color];
[COLOR=#0000FF]for[/color] [COLOR=#0000FF]my[/color] $id ([COLOR=#FF0000]grep[/color] $hash{$_} =~ /$query_string/i, [COLOR=#FF0000]keys[/color] %hash) {
	$flag = [COLOR=#FF0000]1[/color];
	[COLOR=#FF0000]print[/color] [COLOR=#808080]"$id\t$hash{$id}\n"[/color];
}
[COLOR=#FF0000]print[/color] [COLOR=#808080]"No matching results!\n"[/color] [COLOR=#0000FF]unless[/color] $flag;

- Andrew
Text::Highlight - A language-neutral syntax highlighting module in Perl
also on SourceForge including demo

 

[PaulTEG]

thx for the invite, at least the door's in now, so that should help with your headache/colour dilemma

Paul
------------------------------------
Spend an hour a week on CPAN, helps cure all known programming ailments ;-)

 

[KevinADC]

a twist on icrf's code:

my @results = grep {/$query_string/i} values %hash;     
print "No matching results!\n" unless @results;