FAQ 4.45 How do I find the first array element for which a condition is true?
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4.45: How do I find the first array element for which a condition is true?
To find the first array element which satisfies a condition, you can use
the "first()" function in the "List::Util" module, which comes with Perl
5.8. This example finds the first element that contains "Perl".
use List::Util qw(first);
my $element = first { /Perl/ } @array;
If you cannot use "List::Util", you can make your own loop to do the
same thing. Once you find the element, you stop the loop with last.
my $found;
foreach ( @array ) {
if( /Perl/ ) { $found = $_; last }
}
If you want the array index, you can iterate through the indices and
check the array element at each index until you find one that satisfies
the condition.
my( $found, $index ) = ( undef, -1 );
for( $i = 0; $i < @array; $i++ ) {
if( $array[$i] =~ /Perl/ ) {
$found = $array[$i];
$index = $i;
last;
}
}
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