-- main::(gcd.pl:18)
die sprintf "Need two integer arguments, got %d", scalar(@ARGV) unless 
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 to a caller in the stack trace (an older frame). 0
  is the most recent frame. If no count is given, move up 1. This is same as
  "down", but moving in the opposite direction.

 Examples:
     up        # Set current frame to the caller of this current one
     up 1      # Same as above
     up -1     # Same as down

 See also:
  "down", "frame", and "backtrace"

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

  Move the current frame up to a caller in the stack trace (an older frame). 0
  is the most recent frame. If no count is given, move up 1. This is same as
  "down", but moving in the opposite direction.

 Examples:
     up        # Set current frame to the caller of this current one
     up 1      # Same as above
     up -1     # Same as down

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