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...";
}

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In reply to Re^3: loop problem by stevieb
in thread loop problem by WisDomSeeKer34

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