Question

It’s a very simple question. Is

if q and r:

always guaranteed to be equivalent to this?

if q:
  if r:

Answer 1

Python’s and and or are short-circuiting operators, so yes: in your example, if “q” is false, then the interpreter will not evaluate “r”.

edit — after a little thought it occurs to me that it’s important to note that Python’s and and or work kind-of like Javascript && and ||. They do not produce a boolean result. In other words, the operands (“q” and “r”) when evaluated are sort-of “internally” cast to boolean, but that’s just to see how execution should proceed. Thus, if “q” and “r” are both non-empty strings, the result of q and r is the string value of “r”, not boolean true. However, when used in the context given (an if statement), the if statement itself is going to cast the result to boolean in order to make its own control flow decision, so the answer for this example is still “yes” 🙂