Updated Mar 30, 2007 by cdiggins
Labels:	CodeExample, Glossary

Currying

Currying explanation and code example.

Currying

Currying is the technique of generating a function from another function by binding one or more arguments to a specific value.

For example given an addition function which takes two argument, I can create an increment function which takes one value by currying the value one as follows:

define inc
{ [1 add] eval }

A generic function which binds any argument to any function, i.e. a curry function, looks like the following in Cat:

define curry 
{ [quote] dip compose }

Another increment function can be defined as follows:

define inc
{ 1 [add] curry eval }

The type signature of the curry function is:

curry : ('a ('B 'a -> 'C) -> ('B -> 'C))

Comment by joakim.ahnfelt, Jan 03 (6 days ago)

An illustrative example (from the concatenative.org wiki I think):

>>>1 [add]
stack: 1 [add]
>>>curry
stack: [1 add]

Currying simply prepends the value to the quotation.