How can I write code using FP

[kernel1983]

In Function Program£¬Langua ge can use like this:

define a function:
f = lambda x,y:x,y

then we use f to define another function:
f2 = f(1)
the f2 should equal to:
f2=lambda y:1,y

we should be able call f2 with one parameter:f2(2)
just return 1,2

but how can I implement the characteristic in Python??I think it could
do like this but HOW-TO?

thanks~~~
I'm a English beginner!
I wish somebody understand my meaning

[Dan Bishop]

On Jan 16, 9:18 pm, "kernel1983 " <kernel1...@gma il.comwrote:

In Function Program£¬Langua ge can use like this:

define a function:
f = lambda x,y:x,y

then we use f to define another function:
f2 = f(1)
the f2 should equal to:
f2=lambda y:1,y

we should be able call f2 with one parameter:f2(2)
just return 1,2

but how can I implement the characteristic in Python??I think it could
do like this but HOW-TO?

thanks~~~
I'm a English beginner!
I wish somebody understand my meaning

If I understand correctly, you can do:

f = lambda x, y: (x, y)
f2 = lambda y: f(1, y)

[Alejandro Dubrovsky]

kernel1983 wrote:

In Function Program?Languag e can use like this:

define a function:
f = lambda x,y:x,y

then we use f to define another function:
f2 = f(1)
the f2 should equal to:
f2=lambda y:1,y

we should be able call f2 with one parameter:f2(2)
just return 1,2

but how can I implement the characteristic in Python??I think it could
do like this but HOW-TO?

If you are using python 2.5, then you can use functools.parti al, otherwise
lookup one of the many curry implementations , like the ones found in
http://aspn.activestate.com/ASPN/Coo...n/Recipe/52549

One found in the comments of that page by Scott David Daniels:

def curry(*args, **kwargs):
function, args = args[0], args[1:]
def result(*rest, **kwrest):
combined = kwargs.copy()
combined.update (kwrest)
return function(*args + rest, **combined)
return result
so, in your case:

f = lambda x,y: (x,y)
f2 = functools.parti al(f,1)

>>f2(3)

1,3

[kernel1983]

yeah! that's easy! althought no so clear

a = lambda x,y:(x,y)
b = lambda y:a(1,y)

a(1,2)
(1,2)

b(2)
(1,2)

On 1ÔÂ17ÈÕ, ÏÂÎç12ʱ10·Ö, Alejandro Dubrovsky
<dubrov...@phys ics.uq.edu.auwr ote:

kernel1983 wrote:

In Function Program?Languag e can use like this:

define a function:
f = lambda x,y:x,y

then we use f to define another function:
f2 = f(1)
the f2 should equal to:
f2=lambda y:1,y

we should be able call f2 with one parameter:f2(2)
just return 1,2

but how can I implement the characteristic in Python??I think it could
do like this but HOW-TO?If you are using python 2.5, then you can use functools.parti al, otherwise

lookup one of the many curry implementations , like the ones found inhttp://aspn.activestat e.com/ASPN/Cookbook/Python/Recipe/52549

One found in the comments of that page by Scott David Daniels:

def curry(*args, **kwargs):
function, args = args[0], args[1:]
def result(*rest, **kwrest):
combined = kwargs.copy()
combined.update (kwrest)
return function(*args + rest, **combined)
return result

so, in your case:

f = lambda x,y: (x,y)
f2 = functools.parti al(f,1)>>f2(3)1 ,3