raise statement on a conditional expression
If you absolutely want to raise in an expression, you could do
def raiser(ex): raise exreturn <value> if <bool> else raiser(<exception>)This "tries" to return the return value of raiser(), which would be None, if there was no unconditional raise in the function.
Inline/ternary if is an expression, not a statement. Your attempt means "if bool, return value, else return the result of raise expression" - which is nonsense of course, because raise exception is itself a statement not an expression.
There's no way to do this inline, and you shouldn't want to. Do it explicitly:
if not bool: raise MyExceptionreturn value
I like to do it with assertions, so you emphasize that that member must to be, like a contract.
>>> def foo(self):... assert self.value, "Not Found"... return self.value