python assert with and without parenthesis

Question

Here are four simple invocations of assert:

>>> assert 1==2
Traceback (most recent call last):
  File \"\", line 1, in ?
AssertionError

&g         


        

Answer 1

Following is cited from the python doc

Assert statements are a convenient way to insert debugging assertions into a program:

assert_stmt ::= "assert" expression ["," expression]

The simple form, assert expression, is equivalent to if __debug__: if not expression: raise AssertionError

The extended form, assert expression1, expression2, is equivalent to if __debug__: if not expression1: raise AssertionError(expression2)

So when you're using parenthesis here, you're using the simple form, and the expression is evaluated as a tuple, which is always True when being casted to bool