-- main::(gcd.pl:18)
die sprintf "Need two integer arguments, got %d", scalar(@ARGV) unless 
    @ARGV == 2;
set max width is 80.
*** You must alias to a command name, and 'foo' isn't one.
New alias 'yy' for command string 'step' created.
New alias 'evd' for command string 'set display eval' created.
Eval result display style is dumper.
evd: set display eval
*** Command 'set display eval' needs at least 1 argument(s); got 0.
Eval result display style is dumper.
Alias 'evd' for command string 'set display eval dumper' replaced old alias for 'set display eval'.
Eval result display style is dumper.
New alias 'upper' for command string 'up' created.
  up [*count*]

  Move the current frame up in the stack trace (to an older frame). 0 is the
  most recent frame. If no count is given, move up 1.

  See also "down" and "frame".

  Aliases:
upper
Alias for upper removed.
  up [*count*]

  Move the current frame up in the stack trace (to an older frame). 0 is the
  most recent frame. If no count is given, move up 1.

  See also "down" and "frame".
set auto eval is off.
*** Undefined command: "upper". Try "help".
trepan.pl: That's all, folks...