def add(x, y):

return x + y

print(add(5, 7))

# -- Written as a lambda --

add = lambda x, y: x + y

print(add(5, 7))

# Four parts

# lambda

# parameters

# :

# return value

# Lambdas are meant to be short functions, often used without giving them a name.

# For example, in conjunction with built-in function map

# map applies the function to all values in the sequence

def double(x):

return x * 2

sequence = [1, 3, 5, 9]

doubled = [

double(x) for x in sequence

] # Put the result of double(x) in a new list, for each of the values in `sequence`

doubled = map(double, sequence)

print(list(doubled))

# -- Written as a lambda --

sequence = [1, 3, 5, 9]

doubled = map(lambda x: x * 2, sequence)

print(list(doubled))

# -- Important to remember --

# Lambdas are just functions without a name.

# They are used to return a value calculated from its parameters.

# Almost always single-line, so don't do anything complicated in them.

# Very often better to just define a function and give it a proper name.