Why does Python assignment not return a value?

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There are many who feel that having assignments be expressions, especially in languages like Python where any value is allowable in a condition (not just values of some boolean type), is error-prone. Presumably Guido is/was among those who feel that way. The classic error is:

if x = y: # oops! meant to say ==

The situation is also a bit more complicated in Python than it is in a language like C, since in Python the first assignment to a variable is also its declaration. For example:

def f():
    print x

def g():
    x = h()
    print x

In these two functions the “print x” lines do different things: one refers to the global variable x, and the other refers to the local variable x. The x in g is local because of the assignment. This could be even more confusing (than it already is) if it was possible to bury the assignment inside some larger expression/statement.

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