Re: [Haskell-cafe] Is there a name for this property: x + x - x == x

Exactly, it's 3 properties: associativity, inverse and identity. On Wed, Jun 4, 2014 at 11:42 AM, David Thomas wrote:

If you have associativity, this seems roughly the same as saying there is an additive inverse for every x, because x + x - x = x => x + (x - x) = x => x + 0 = x.

On Wed, Jun 4, 2014 at 7:34 AM, Omari Norman wrote:

...

It's not quite idempotence, because more than one function is involved.

It's a common property and I figure I can write a higher order function to build QuickCheck tests for it. I was just wondering if it has a name.

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