Programming Erlang, 2nd Edition

Operator Precedence

Table 5, ​Operator precedence​ shows all the Erlang operators in order of descending priority together with their associativity. Operator precedence and associativity are used to determine the evaluation order in unparenthesized expressions.

Table 5. Operator precedence

Operators	Associativity
:
#
(unary) +, (unary) -, bnot, not
/, *, div, rem, band, and	Left associative
+, -, bor, bxor, bsl, bsr, or, xor	Left associative
++, - -	Right associative
==, /=, =<, <, >=, >, =:=, =/=
andalso
orelse
= !	Right associative
catch

Expressions with higher priority (higher up in the table) are evaluated first, and then expressions with lower priority are evaluated. So, for example, to evaluate 3+4*5+6, we first evaluate the subexpression 4*5, since ( ...