[Haskell-cafe] Could someone teach me why we use Data.Monoid?
stephen.tetley at gmail.com
Fri Nov 13 11:48:25 EST 2009
2009/11/13 Rafael Gustavo da Cunha Pereira Pinto <RafaelGCPP.Linux at gmail.com>:
> Monoid is the category of all types that have a empty value and an append
Or more generally a neutral element and an associative operation:
The multiplication monoid (1,*)
9*1*1*1 = 9
1 is neutral but you might be hard pressed to consider it _empty_.
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