On Sat, 18 Aug 2012 20:52:01 -0700 Walter Bright <newshou...@digitalmars.com> wrote:
> On 8/18/2012 8:31 PM, Adam D. Ruppe wrote: > > enum BOOL { > > TRUE, > > FALSE, > > FILE_NOT_FOUND > > } Heh, that's probably the #1 classic Daily WTF :) > > I used to work with digital electronics. There, "boolean" logic > actually had 4 states: > > True > False > Don't Know > Don't Care > It sounds like it's some EE joke, but yea, strange as it seems, not only is there really a "Don't care", but it's actually useful (for not wasting excess silicon/logic-gates on states that can't (or shouldn't) ever occur - it means "ehh, just make this whatever value would require the fewest logic gates since it won't actually matter anyway"). I only ever dabbled with some very rudimentary digital EE, I'm still a bit of a novice, but it's pretty damn cool stuff.