Hello all. Perl seems to be tripping me up on the basics.. Anyway, I have this basic while loop, which has the responsibility of checking 'STDIN' for either two specific characters. If they are not entered, the while loop asks the user for input again, until one of the characters is entered: 
# - ask the user whether or not they would like to align their sequenc
+es Locally or Globally
    print $username . ", would like to align your protein sequences gl
+obally or locally? (enter either 'g' or 'l') ";
    $alignment_type = <STDIN>;
    # - debug
    print "\n", $alignment_type, "\n";
    # - debug

    while( ($alignment_type ne 'g') or ($alignment_type ne 'l') ){
    
        print $username . ", your selection was incomprehensible (ente
+r either 'globally' or 'locally'): ";
        $alignment_type = <STDIN>;
    }
    print "\n";

[download]
Even if either 'g' or 'l' are entered, the code always gets trapped in the loop. Confused...

In reply to Basic 'while' loop problem by BioBoy

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