ETOOBUSY 🚀 minimal blogging for the impatient
use VERSION - but how?
It’s fine to
use v5.X.Ywith the
vwhen asking for a minimum
perlversion and its related features.
More and more in the past days I read about setting a
use v5.X or
v5.X.Y line early in Perl programs, just to get all benefits of
perl version out of the box.
This started to itch a bit after some time because in all those places
they were suggesting to use the v-string form, i.e. prefixing the
version with the letter
v. The itch was that I was used to using:
use 5.024; # no "v", and a "0" before "24"
instead, for reasons that I understood at the time I chose this form, but that I obviously obliviated on the spot.
So, what’s better? It turns out that putting the
v is, in 2021, mostly
fine. Well, totally fine in my (new) opinion.
From the use documentation:
Specifying VERSION as a numeric argument of the form 5.024001 should generally be avoided as older less readable syntax compared to v5.24.1. Before perl 5.8.0 released in 2002 the more verbose numeric form was the only supported syntax, which is why you might see it in
use v5.24.1; # compile time version check use 5.24.1; # ditto use 5.024_001; # ditto; older syntax compatible with perl 5.6
So there you have it, I was using the
5.024 form just to make sure that
perl from middle ages would properly parse it and, in any case,
complain that it could not execute it.
Additional elaborations regarding version numbers (although on the
setting side, not on the
useing side) can be found here: Version
numbers should be boring.
Bottom line: it’s fine to
use v5.X.Y; with the
v to settle for a
perl version in 2021.