Li Chen wrote:

/ ...

> irb(main):001:0> File:file?(ruby.rb)
> SyntaxError: compile error
> (irb):1: parse error, unexpected '(', expecting $
> File:file?(ruby.rb)
>            ^
>         from (irb):1

You must put quotation marks around the file name.

-- 
Paul Lutus
http://www.arachnoid.com