Proposal: Data.Bool.implies

Henning Thielemann lemming at
Mon Jan 18 18:38:01 UTC 2016

On Mon, 18 Jan 2016, Brent Yorgey wrote:

> I disagree.  The equivalence between `implies` and (<=) depends on the 
> ordering chosen for Bool, which is completely arbitrary, and is not 
> something people thinking about logic should be expected to know or 
> learn.  For example, the Coq standard library happens to choose the 
> other order, with True < False.

I can confirm that the order is arbitrary. I used a Modula II 
implementation where True was represented as -1, because that is the bit 
pattern where all bits are set.

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