Re: how can I get localtime without mutating any variables

Presuming your problem is that you don't want the pieces where you're now using $_ you'd either use undef in those locations, or use a slice and pull out just the ones you're actually interested in; e.g.

(undef, $min, $hr, $day, $mon, $year) = localtime();
($min, $hr) = (localtime())[1,2];
[download]

You may also want to consider DateTime or Time::Piece to provide an object interface instead.

The cake is a lie.
The cake is a lie.
The cake is a lie.

Comment on Re: how can I get localtime without mutating any variables Select or Download Code

Replies are listed 'Best First'.
Re^2: how can I get localtime without mutating any variables by thirtySeven (Acolyte) on Jan 06, 2021 at 20:37 UTC
no the problem was not with the "$_" variables but rather with the fact that I was changing the $yr $day, etc variables. It seems that using a slice worked though.	[reply]
Re^3: how can I get localtime without mutating any variables by LanX (Saint) on Jan 06, 2021 at 20:45 UTC
you had the right idea, but better replace `$_` with `undef` from perlfunc#my-VARLIST Note that with a parenthesised list, undef can be used as a dummy placeholder, for example to skip assignment of initial values: `my ( undef, $min, $hour ) = localtime;` [download] you can always use `undef` on the left-hand-side to ignore assignments. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re^3: how can I get localtime without mutating any variables by Marshall (Canon) on Jan 07, 2021 at 01:05 UTC
This reply is hard for me to understand. The whole idea of this is to set the $yr and $day, etc. variables! `my (undef, $min, $hr, $day, $mon, $year) = localtime();` [download] and `my ($min, $hr, $day, $mon, $year) = (localtime())[1..5];` [download] mean exactly the same thing. Perhaps one point of confusion is that your statements like `my $year;` are completely unnecessary. That creates the variable $year and assigns it the value of undef. In general, combine the creation of the variable and the assignment of useful value to it into one statement. There is no need to have a list of `my $year;` type of statements before assigning values to them. Also limit the use of these newly created "my" variables to the smallest scope practical. In general, $_ , the "default variable", "belongs to Perl" - meaning that is something Perl sets and you read, but you never set or write to yourself. There are of course exceptions to this. However, for your first few hundred programs, you are unlikely to happen across one of these exceptions.	[reply] [d/l] [select]


laziness, impatience, and hubris
	PerlMonks