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Not quite, that is partial application. Actual currying would allow you to do partial application this way, making it less explicit: > g = f(3) # no second p

Not quite, that is partial application. Actual currying would allow you to do partial application this way, making it less explicit: > g = f(3) # no second parameter provided g = <unary function> # however it would be indicated in the python shell To get it in Python you'd need to do this: f = lambda x: lambda y: x + y g = f(3) # result is a function, or funcallable, or whatever Python calls the resultant type This makes the currying explicit. In general, currying is taking an n-ary function and reducing it to a series of n unary functions. These three are equivalent, in Haskell(ish, rusty): f x y = x + y g x = \y -> x + y h = \x -> \y -> x + y In Haskell, you don't have to use the explicit form of `h` (or the explicit form in the Python example) if you don't want to (and it would probably be weird if you used it extensively).

thaumasiotes 4y ago
> Actual currying would allow you to do partial application this way, making it less explicit > To get it in Python you'd need to do this: > f = lambda x: lambda y: x + y > This makes the currying explicit. In general, currying is taking an n-ary function and reducing it to a series of n unary functions. Something's gone wrong; your example of explicit currying conflicts with your definition of currying. `f` is a unary function.
- Jtsummers 4y ago
  The original `f` was a binary function: f = lambda x, y: x + y My updated curried `f` is a unary function, but it returns a unary function itself: f = lambda x: lambda y: x + y That's what currying is. I just reused the name, if you prefer: curried_f = lambda x: lambda y: x + y EDIT: And note, it makes the partial application less explicit/verbose than the original, but the currying is very explicit because of Python's syntax. g = curried_f(3) Is "just" a function call, while: g = lambda y: f(3, x) does the same thing (functionally, at least) but the partial application is made explicit.

thaumasiotes 4y ago

> Actual currying would allow you to do partial application this way, making it less explicit > To get it in Python you'd need to do this: > f = lambda x: lambda y: x + y > This makes the currying explicit. In general, currying is taking an n-ary function and reducing it to a series of n unary functions. Something's gone wrong; your example of explicit currying conflicts with your definition of currying. `f` is a unary function.

Jtsummers 4y ago
The original `f` was a binary function: f = lambda x, y: x + y My updated curried `f` is a unary function, but it returns a unary function itself: f = lambda x: lambda y: x + y That's what currying is. I just reused the name, if you prefer: curried_f = lambda x: lambda y: x + y EDIT: And note, it makes the partial application less explicit/verbose than the original, but the currying is very explicit because of Python's syntax. g = curried_f(3) Is "just" a function call, while: g = lambda y: f(3, x) does the same thing (functionally, at least) but the partial application is made explicit.