2.1.2. Boolean Operations

Operation

Result --- Notes

x or y

if x is false, then y, else x --- (1)

---

x and y

if x is false, then x, else y --- (1)

---

not x

if x is false, then 1, else 0 --- (2)

(1)

These only evaluate their second argument if needed for their outcome.

(2)

`not' has a lower priority than non-Boolean operators, so e.g. not a == b is interpreted as not(a == b), and a == not b is a syntax error.