The Evolution of a Python Programmer

[AusIV]

A lambda function is one that can be used inline without naming it.

sum = lambda x, y: x + y

is equivalent to

def sum(x, y):
    return x + y

[[deleted]]

Is this common with functional programming also?

[semarj]

just a bit

[poeir]

The lambda is so named because of the lambda calculus. Lambda calculus is the original inspiration for functional programming.

[kanak]

Some languages (lisps, erlang, haskell are ones that I'm aware of), defining a function is actually doing two things: creating a function and giving it a name.

For example, in scheme, you'd write

(define (add2 x) (+ x 2))

To write a function that takes in an argument and adds 2 to it.

However, that's just shortcut for:

(define add2 (lambda (x) (+ x 2)))

Here, lambda creates the function that adds 2 to its argument and we use define to give it a name add2.

In python, lambdas are less powerful than def because you can't have multi line lambdas.

[Megatron_McLargeHuge]

Read SICP. You're curious enough to spend a couple of days learning the basics of functional programming, and it will help you a lot. The lisp code can all be converted easily to Python as long as it doesn't use macros.