Operator precedence

Operator precedence determines how operators are parsed concerning each other. Operators with higher precedence become the operands of operators with lower precedence.

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Associativity

Associativity determines how operators of the same precedence are parsed. For example, consider an expression:

a OP b OP c

Left-associativity (left-to-right) means that it is processed as (a OP b) OP c, while right-associativity (right-to-left) means it is interpreted as a OP (b OP c). Assignment operators are right-associative, so you can write:

a = b = 5;

with the expected result that a and b get the value 5. This is because the assignment operator returns the value that is assigned. First, b is set to 5. Then the a is also set to 5, the return value of b = 5, aka right operand of the assignment.

Examples

3 > 2 && 2 > 1
// returns true

3 > 2 > 1
// returns false because 3 > 2 is true, then true is converted to 1 in inequality operators, therefore true > 1 => 1 > 1 which is false
// Adding parentheses makes things clear: (3 > 2) > 1

Table

The following table is ordered from highest (21) to lowest (1) precedence.