A 'constant' is useful - perhaps - because you can't accidentally change it. Method 1 achieves this, whereas method two is no more 'constant' than: my ($min_char, $max_char) = (1,12);

You are free to change the values of your %constant hash anywhere within its lexical scope. The only advantage of your method 2 is the implicit "Don't change these, they are constants" nomenclature of the hash. You can use a sub to generate a 'constant' like this: 

sub MIN { return 1  }
sub MAX { return 12 }

[download]

This generates 'constants' but suffers from the same formatting woes as use constant in that you can't interpolate a sub into a double quoted string. You may like this formatting using printf more: 

sub MIN { 1  }  # could just as easily be 'use constant MIN => 1;'
sub MAX { 12 }
printf "x %d - %d x", MIN, MAX;

[download]

I have dropped the return as a sub returns the last value it evaluates and I am inherently lazy.

Otherwise use normal lexically scoped variables to make it pretty: 

my ($min, $max) = (1,12);
print "x $min - $max x";

[download]

These are your choices, it's up to you what you prefer. One of the common conventions is to use ALL_CAPS for constants which is important if these constants are actually variables and we are depending on programmer goodwill not to change them. Swings and roundabouts. TIMTOWDI

cheers

tachyon

s&&rsenoyhcatreve&&&s&n\w+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: Use constant vs. hashes by tachyon
in thread Use constant vs. hashes by legLess

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