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The binding of operators in C and C++ is specified (in the corresponding Standards) by a factored language grammar, rather than a precedence table. This creates some subtle conflicts. For example, in C, the syntax for a conditional expression is:
Dennis Ritchie, creator of the C language, said of the precedence in C (shared by programming languages that borrow those rules from C, for example, C++, Perl and PHP) that it would have been preferable to move the bitwise operators above the comparison operators. [42]
The associativity and precedence of an operator is a part of the definition of the programming language; different programming languages may have different associativity and precedence for the same type of operator. Consider the expression a ~ b ~ c. If the operator ~ has left associativity, this expression would be interpreted as (a ~ b) ~ c.
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In computer science, an operator-precedence parser is a bottom-up parser that interprets an operator-precedence grammar.For example, most calculators use operator-precedence parsers to convert from the human-readable infix notation relying on order of operations to a format that is optimized for evaluation such as Reverse Polish notation (RPN).
The precedence of the conditional operator in Perl is the same as in C, not as in C++. This is conveniently of higher precedence than a comma operator but lower than the precedence of most operators used in expressions within the ternary operator, so the use of parentheses is rarely required. [13]
An operator which is non-associative cannot compete for operands with operators of equal precedence. In Prolog for example, the infix operator :-is non-associative, so constructs such as a :- b :- c are syntax errors. Unary prefix operators such as − (negation) or sin (trigonometric function) are typically associative prefix operators.
For example, consider variables a, b and c of some user-defined type, such as matrices: a + b * c. In a language that supports operator overloading, and with the usual assumption that the '*' operator has higher precedence than the '+' operator, this is a concise way of writing: Add(a, Multiply(b, c))