PilotinControl:
If you're just wanting to simplify conditional statements like the ones you've shown, I typically use a function like this:
use strict;
use warnings;
sub between {
my ($min, $val, $max) = @_;
return $val>=$min && $val<=$max;
}
for my $range (450, 475, 500, 550, 450, 350, 250, 100) {
print "Range: $range\n";
if (between(300, $range, 400)) {
exit;
}
if (between(425, $range, 500)) {
print "LIGHTS ON\n";
}
}
$ perl t.pl
Range: 450
LIGHTS ON
Range: 475
LIGHTS ON
Range: 500
LIGHTS ON
Range: 550
Range: 450
LIGHTS ON
Range: 350
If you need to get fancier and build your functions dynamically (such as reading the values from a file), I tend to use a closure to generate them:
#!/usr/bin/env perl
use strict;
use warnings;
# Build the functions
my @tests;
while (<DATA>) {
my ($min, $max, $message) = split /\s+/, $_, 3;
push @tests, make_test_function($min, $max, $message);
}
my $range = 0;
while ($range < 600) {
print "Range: $range\n";
for my $test (@tests) {
$test->($range);
}
$range += int(100*rand);
}
sub make_test_function {
my ($min, $max, $message) = @_;
return sub {
my $val = shift;
print $message if $val >= $min and $val <= $max;
}
}
__DATA__
100 350 In range A
200 500 In range B
300 400 In range C
$ perl t.pl
Range: 0
Range: 10
Range: 10
Range: 25
Range: 56
Range: 144
In range A
Range: 208
In range A
In range B
Range: 254
In range A
In range B
Range: 323
In range A
In range B
In range C
Range: 379
In range B
In range C
Range: 468
In range B
Range: 530
Range: 550
Range: 557
...roboticus
When your only tool is a hammer, all problems look like your thumb. | 