Introduction. Precedence of operators decides the order of execution of operators in an expression. For example in 2+6/3, division of 6/3 is done first and then addition of 2+2 takesplace because division operator / has higher precedence over addition operator +.

logical-AND operator
The logical-AND operator ( && ) has higher precedence than the logical-OR operator ( || ), so q && r is grouped as an operand.

The best way to force your own operator precedence is to place parentheses around subexpressions to which you wish to give high precedence. Operator associativity refers to the direction of processing (left-to-right or right-to-left).

The precedence of an operator specifies how “tightly” it binds two expressions together. Operators of equal precedence that are non-associative cannot be used next to each other, for example 1 < 2 > 1 is illegal in PHP.

Operator precedence determines the order in which operators are evaluated. Operators with higher precedence are evaluated first. A common example: 3 + 4 * 5 // returns 23. The multiplication operator (” * “) has higher precedence than the addition operator (” + “) and thus will be evaluated first.

Since normal function application in Haskell (i.e. the juxtaposition of terms, not the $ operation) is left associative in my opinion function composition should also be left associative. After all most people in the world (including myself) are used to reading from left to right.

LOWEST PRECEDENCE The compound logical operators, &&, ||, -a, and -o have low precedence. The order of evaluation of equal-precedence operators is usually left-to-right.

Operator precedence determines which operator is performed first in an expression with more than one operators with different precedence. Operators Associativity is used when two operators of same precedence appear in an expression. Associativity can be either Left to Right or Right to Left.

Precedence of operators decides the order of execution of operators in an expression. For example in 2+6/3, division of 6/3 is done first and then addition of 2+2 takesplace because division operator / has higher precedence over addition operator +. To force a certain operator to be called before other, parentheses should be used.

Operator precedence and associativity only determine how expressions are grouped, they do not specify an order of evaluation.

The precedence of an operator specifies how “tightly” it binds two expressions together. For example, in the expression 1 + 5 * 3, the answer is 16 and not 18 because the multiplication (“*”) operator has a higher precedence than the addition (“+”) operator.

The @ symbol is the error control operator (aka the “silence” or “shut-up” operator). It makes PHP suppress any error messages (notice, warning, fatal, etc) generated by the associated expression. It works just like a unary operator, for example, it has a precedence and associativity. Below are some examples: