in reply to loop problem

Where is your loop?

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Re^2: loop problem
by WisDomSeeKer34 (Sexton) on Jun 12, 2018 at 16:55 UTC
    There is no loop in this code. I tried it with a submodule. Like this: 
    #!/usr/bin/env perl

# use strict;
use warnings;
use utf8;
use feature "say";
use Math::Trig;

sub intro {
say "What is the radius?";
our $radius= <STDIN>;
chomp ($radius);
our $a = 2*pi;
our $c = $radius * $a
}

intro();

if ($radius==0) {
   say "circumference= ", $radius;
}

elsif ($radius<0) {
    say "Radius should be greater than 0";
    intro();
}

else {
   say "circumference= ", $c
}

    [download]

    But you have to switch off the strict command to make it work. And then it still doesn't work like I want it to.

    How to create the loop I want?

[reply]
[d/l]
      I tried it with a submodule.

      In this context, the proper word for "submodule" is "subroutine."

      Give a man a fish:  <%-{-{-{-<

[reply]
[d/l]

      What error does strict throw? Works fine for me as-is on 5.26.1.

      Anyway, here's an example of how to get what you want:

      my $radius = -1;

until ($radius >= 0){
    say "What is the radius?";
    $radius= <STDIN>;
    chomp ($radius);
    say "radius must be >= 0. Try again...";
}

      [download]
[reply]
[d/l]
[select]

        Regarding your question: if I run the program with the submodule with strict, I get this output:

        Variable "$radius" is not imported at circum1.pl line 19.
Variable "$radius" is not imported at circum1.pl line 20.
Variable "$radius" is not imported at circum1.pl line 23.
Variable "$c" is not imported at circum1.pl line 30.
Global symbol "$radius" requires explicit package name (did you forget
+ to declare "my $radius"?) at circum1.pl line 19.
Global symbol "$radius" requires explicit package name (did you forget
+ to declare "my $radius"?) at circum1.pl line 20.
Global symbol "$radius" requires explicit package name (did you forget
+ to declare "my $radius"?) at circum1.pl line 23.
Global symbol "$c" requires explicit package name (did you forget to d
+eclare "my $c"?) at circum1.pl line 30.
Execution of circum1.pl aborted due to compilation errors.

        [download]
        And thank you for answering my question.
[reply]
[d/l]

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