i was wondering if there was a faster way to set those below
Max_age = 21
Suzy_age = 21
Mia_age = 21
why not writing
Max_age and Suzy_age and Mia_age = 21
or even
Max_age = Suzy_age = Mia_age = 21
I'm new to python and this kind of code seems really intuitive, but somehow there's no one liner like thoses ? am i wrong ? please tell me i'm wrong.
The first one is invalid
a and b and c = 1
will cause an error, since a and b is a binary expression, which is a value, not a variable, so you can't assign to it.
the second one is valid
a = b = c = 1
will run as in the order
a = (b = (c = 1))
since the assignment is right-associative. The assignment c = 1 evaluates to 1, so that will be assigned to b, and so on.
However, in python it's common to write multiple assignments like
a, b, c = 1, 2, 3
which is called tuple unpacking
Whether that's preferable to having one assignment per line, is a matter of style and context.
a is assigned first, then b, then c.)
a = (b = (c = 1)) is not a valid python statement as you can't assign a value to a global variable definition. a = b = c = 1 is a separate python syntax rule.
a is assigned to the result of the expression b = .... So, the right expression has to be evaluated first. How could a be assigned first?b = ... is not an expression at all. Assignments are statements, and they're executed left-to-right.
1 and each of a, b and c is a target list, meaning that a=b=c=1 sets a directly to 1, then b directly to 1 and c directly to 1, in that order. Parsing the expression using ast, or disassembling it using dis will both demonstrate that b is not set to the value of the subexpression c=1 for example.You can do so:
Max_age, Suzy_age, Mia_age = 21, 21, 21
Max_age, Suzy_age, Mia_age = [21] * 3
Max_age = Suzy_age = Mia_age = 21is already valid.