Ad hoc currying in Scheme (1)

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Lecture 4 - Page 24 : 34

Functional Programming in Scheme
Higher-order Functions

Ad hoc currying in Scheme (1)

It is possible to achieve 'the currying effect' by generalizing functions, which requires two or more parameters, to only require a single parameter

Motivation:

Expression	Value
(map li (list "one" "two" "three"))	("<li>one</li>" "<li>two</li>" "<li>three</li>")
(define li-mapper (map li))	map: expects at least 2 arguments, given 1
(define li-mapper ((curry2 map) li)) (li-mapper (list "one" "two" "three"))	("<li>one</li>" "<li>two</li>" "<li>three</li>")

A legal mapping and an impossible attempt to curry the mapping function. The last example shows an application of curry2 to achieve the wanted effect, but as it appears, the solution is not very elegant.

The function curry-generalized.

This is a higher-order function which generalizes the function passed as parameter to curry-generalized. The generalization provides for just passing a single parameter to f, in the vein of currying.