[Haskell-cafe] Overload function application? (was: foldr (.) id)

[wren ng thornton]

On 10/27/12 3:23 PM, Greg Fitzgerald wrote:
> Should library functions target Control.Category?  We write for Num,
> IsString, and ListLike.  Haskell overloads number literals and string
> literals, and awkwardly not List literals.  Should Haskell overload
> function application too?
>
> How cool would it be to be able to leverage all of Haskell's libraries, and
> effectively none of the runtime, by implementing instances for literals and
> function application?  Say, for example, to generate a call graph, or make
> the language strict, or target LLVM more directly.  Anyone tried this?

Categories, as such, don't have any notion of application. There's just 
the identity morphism and morphism composition.

Overloaded application is more the purview of Applicative, whence the 
name (<$>) as a generalization of ($).

-- 
Live well,
~wren