s/\((.*)\)/$1/;		# strip brackets
    my @args = split (/,/);	# split arguments

    $_ = $args[0];		# get component type

    # select rule to use
    if (/EMTF|emtf/)	{ $retval = lcos_emtf	(@args); }
    if (/^EMTF|emtf$/)	{ $retval = lcos_emtf	(@args); }
    
    # if a substitution has been made ($retval)
    if ($retval)
    {
	return $retval;		# return substituted expression
    }
    else			# return nothing