Expressions

Values are the most primitive type of expressions.

More complicated expressions are formed from values using various operators.

Numerical constants in the NXT are represented as integers or floating point values. The type depends on the value of the constant. NXC internally uses 32 bit floating point math for constant expression evaluation. Numeric constants are written as either decimal (e.g. 123, 3.14) or hexadecimal (e.g. 0xABC). Presently, there is very little range checking on constants, so using a value larger than expected may produce unusual results.

Two special values are predefined: true and false. The value of false is zero (0), while the value of true is one (1). The same values hold for relational operators (e.g. <): when the relation is false the value is 0, otherwise the value is 1.

Values may be combined using operators. NXC operators are listed here in order of precedence from highest to lowest.

Operator	Description	Associativity	Restriction	Example
abs()	Absolute value	n/a		abs(x)
sign()	Sign of operand	n/a		sign(x)
++, –	Postfix increment/decrement	left	variables only	x++
++, –	Prefix increment/decrement	right	variables only	++x
-	Unary minus	right		-x
~	Bitwise negation (unary)	right		~123
!	Logical negation	right		!x
*, /, %	Multiplication, division, modulus	left		x * y
+, -	Addition, subtraction	left		x + y
<<, >>	Bitwise shift left and right	left		x << 4
<, >, <=, >=	relational operators	left		x < y
==, !=	equal to, not equal to	left		x == 1
&	Bitwise AND	left		x & y
^	Bitwise exclusive OR	left		x ^ y
|	Bitwise inclusive OR	left		x | y
&&	Logical AND	left		x && y
||	Logical OR	left		x || y
?:	Ternary conditional value	right		x==1 ? y : z

Table 5. Expression Operators

Where needed, parentheses are used to change the order of evaluation:

x = 2 + 3 * 4;  // set x to 14
y = (2 + 3) * 4;        // set y to 20

• Conditions