precedence-of-logical-operators.md

Precedence Of Logical Operators

There are two sets of logical operators that you are going to see in Ruby. The more common and idiomatic set are !, &&, and ||. Relative to all the other operators in the Ruby language, these three have high precedence.

The other set of logical operators are not, and, and or. These ones have relatively much lower precedence. Though they work conceptually the same.

The reason to be aware of the differences in precedence is that if you were to mix the two sets, you could end up with unexpected results.

> not true && false
=> true
> !true && false
=> false

To keep my Ruby code idiomatic and to avoid these kinds of potential logical mixups, I stick to using nearly exclusively the first set—!, &&, and ||.

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