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pythontuplesgenerator

Difference between generator expression and tuple expression

I have 2 statements

# Generator expression
squares_gen = (x**2 for x in range(10))

# Tuple comprehension
squares_tuple = (x**2 for x in range(10))

How does Python understand that the 1st statement is generator and the 2nd one is a tuple?

# Generator expression
squares_gen = (x**2 for x in range(10))

# Tuple comprehension
squares_tuple = (x**2 for x in range(10))

for square in squares_gen:
    print(square)

print(squares_tuple)

I am trying to understand how Python will process them differently

Solution

  • There is no such thing as a tuple comprehension. squares_tuple is still a generator.

    >>> squares_tuple = (x**2 for x in range(10))
>>> type(squares_tuple)
<class 'generator'>

    Because a generator is an iterable value, you can pass it to tuple to create a tuple.

    >>> tuple(squares_tuple)
(0, 1, 4, 9, 16, 25, 36, 49, 64, 81)