Simple maths question

Hello,

I was demonstrating how easy Tcl is to use (or at least to learn to use) when I was immediately flummoxed.

On a Windows XP machine I created a trivial proc:

(bin) 289 % proc subtract {a b} {
return [expr {$a - $b}]
}

(bin) 290 % subtract 3 2.2
0.7999999999999998

Eh? This was using Tcl 8.5a4. It works properly in 8.4.11. Is this a known bug (sorry if it is)?



Thanks,
Frem.

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