Question

For instance, in “Programming Perl”, there are sentences such as this one:

These string operators bind as tightly as their corresponding arithmetic operators.

In other places, both in “PP” and in perldoc, the authors use phrasing such as “binds tightly”; for instance, when referring to =~, or “binds even more tightly” when referring to ** (exponentiation).

If this were the same as precedence, it would not be possible to say things like “even more tightly”, I’m guessing. You’d say “higher/lower precedence” instead.

So what exactly does it mean for an operator to bind?

Answer 1

This refers to operator precedence. In the statement

a = b + c * d

The multiplication has higher precedence, and therefore “binds” more tightly than addition.

Operators that bind more tightly are evaluated before less-tightly bound operators.