Only care about Linux and Win32? Solaris, HP-UX, AIX and other Unix flavors all use clear, not cls. As a HP-UX user I hate being put in the Win32 camp!

In the code shown, it will always use cls, as the value for $^O on Linux is linux, not Linux.

I also test my modules on Win32, so I am not a hater of win32, but having been confronted with tests like this in the past, you'd break more than you fix.

/me counts down to the official perl6 release. Almost X-mas ! :)