Operators

DDMathParser recognizes all common mathematical operators:

Operator	Function	Description
Standard Operators
+	add	addition and unary positive
-	subtract and negate	subtraction and negation
* and ×	multiply	multiplication
/ and ÷	divide	division
%	mod	modulus
!	factorial	factorial
**	pow	exponentiation
Bitwise Operators
&	and	bitwise and
|	or	bitwise or
^	xor	bitwise xor
~	not	bitwise not
<<	lshift	bitwise left shift
>>	rshift	bitwise right shift
Comparison Operators
== or =	l_eq	equal
!=	l_neq	not equal
<	l_lt	less than
>	l_gt	greater than
<= or ≤	l_ltoe	less than or equal
>= or ≥	l_gtoe	greater than or equal
Logical Operators
&& or ∧	l_and	logical and
|| or ∨	l_or	logical or
! or ¬	l_not	logical not

Considerations

Logical Values

The comparison and logical operators both return a boolean value. During evaluation, that boolean value is strictly interpreted as either 0 (false) or 1 (true). For example, @"41 + (1 && 1)" is literally 41 + true, but is evaluated as 42.

On the same note, the operands to the logical operators are also interpreted as booleans (using -[NSNumber boolValue]).

Factorial and Logical Not

Differentiating between factorial (!) and a logical not (!) is difficult. A ! is interpreted as a logical not if:

• it is the first token
• it is preceded by a binary operator
• it is preceded by a right associative unary operator

Otherwise it is treated as a factorial. A ¬ token is always treated as a logical not (for obvious reasons).

Parentheses and Associativity

For simplification in dealing with implicit multiplication, an opening parenthesis is considered a right associative unary operator, and a closing parenthesis is considered a left associative unary operator.