#4189: Add (<.>) operator (generalizing (.) to Functor)

Stephen Tetley stephen.tetley at gmail.com
Mon Aug 2 12:30:01 EDT 2010

On 2 August 2010 14:59, Dan Doel <dan.doel at gmail.com> wrote:
> The point of all of these is that we don't
> conceptualize them as "three parameter functions." They are two parameter
> functions, with the two parameters being functions, and the result being a
> function.

For sure, we don't conceptualize them as 3 parameter functions because
they're more general. But Maciej Piechotka's (<.>) is just a function
so not its as general as the arrow operators.

My point was that in Prelude + subset of Base, infix symbol names are
used for binary functions, not arbitrary combinators like `on` (vis
the three exceptions listed). Whether this is a worthwhile principle
or even whether its just an accident and not a principle is open to
debate. My opinion is that its worth airing it now, as granting a
place in Base for (<.>) would feel like a precedent.

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