def tr_method(method)
case method
when "[]"
"ref_"
when "[]="
"set_"
when "+"
"plus_"
when "+@"
"uplus_"
when "-"
"minus_"
when "-@"
"uminus_"
when "*"
"mul_"
when "/"
"div_"
when "%"
"mod_"
when "**"
"power_"
when "~"
"inv_"
when "=="
"eq_"
when "==="
"eqq_"
when "=~"
"match_"
when "&"
"and_"
when "|"
"or_"
when "<<"
"lshift_"
when ">>"
"rshift_"
when "<=>"
"cmp_"
when "<"
"lt_"
when "<="
"le_"
when ">"
"gt_"
when ">="
"ge_"
when "^"
"xor_"
when "`"
"backquote_"
when /!$/
$` + "_bang"
when /\?$/
$` + "_p"
when /=$/
$` + "_eq"
else
method
end
end