My solution in the past has been either to write 2 functions or else to pull the following trick: 
sub foo {
  my %args = (1 == @_) ? (named_arg => shift) : @_;
  # etc
}

[download]
or pull it as follows: 
sub foo {
  my $args = shift;
  if (! ref($args)) { # <- test depends on usage
    $args = {named_arg => $args);
  }
  # etc
}

[download]
Now it can be called two ways. Internally that is turned into a hash of named arguments, and then I can proceed to supply defaults for whatever is missing.

In reply to Re (tilly) 1: Is it a scalar or a hash? by tilly
in thread Is it a scalar or a hash? by DrZaius

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