rewrite small piece of python code

Question

I have lots of small pieces of code that look like:

for it in <iterable>:
  if <condition>:
     return True/False

Is there a way I can rewrite this piece of code with a lambda expression ? I know I can factor it out in a small method/function, but I am looking for some lambda thing if it can be done.

Answer 1

Use the built-in any function.

e.g.

any(<condition> for it in <iterable>)      # return True on <condition>

Answer 2

Here is a simple example which returns True if any of the objects in it is equal to 2. by using the map function:

any(map(lambda x: x==2, it))

Change the lambda expression to reflect your condition.

Another nice way is to use any with a list comprehension:

any([True for x in it if x==2])

or alternatively, a generator expression:

any(x==2 for x in it)

Answer 3

if you want to check the condition for every item of iterable you can use listcomprehensions to to this

b = [ x == whatever for x in a ]

you can combine this with any if you only need to know if there is one element that evals to true for your condition

b = any(x == whatever for x in a)

Answer 4

In addition to what everyone else has said, for the reverse case:

for it in <iterable>:
  if <condition>:
     return False
return True

use all():

b = all(<condition> for it in <iterable>)