Python Language Tutorial => Reduce

Syntax

Parameter	Details
function	function that is used for reducing the iterable (must take two arguments). (positional-only)
iterable	iterable that's going to be reduced. (positional-only)
initializer	start-value of the reduction. (optional, positional-only)

reduce might be not always the most efficient function. For some types there are equivalent functions or methods:

sum() for the sum of a sequence containing addable elements (not strings):
```
sum([1,2,3])                                 # = 6
```

str.join for the concatenation of strings:

''.join(['Hello', ',', ' World'])            # = 'Hello, World'

next together with a generator could be a short-circuit variant compared to reduce:
```
# First falsy item:
next((i for i in [100, [], 20, 0] if not i)) # = []  
```

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