Numeric Operators
Numeric operators generally follow C styles.
Unary Operators
Operator | Description |
---|---|
+ | positive |
- | negative |
let number = +42;
number = -5;
number = -5 - +5;
-(-42) == +42; // two '-' equals '+'
// beware: '++' and '--' are reserved symbols
Binary Operators
Operator | Description | Result type | Integer | Floating-point | Decimal |
---|---|---|---|---|---|
+ , += | plus | numeric | yes | yes, also integer | yes, also integer |
- , -= | minus | numeric | yes | yes, also integer | yes, also integer |
* , *= | multiply | numeric | yes | yes, also integer | yes, also integer |
/ , /= | divide (integer division if acting on integer types) | numeric | yes | yes, also integer | yes, also integer |
% , %= | modulo (remainder) | numeric | yes | yes, also integer | yes, also integer |
** , **= | power/exponentiation | numeric | yes | yes, also FLOAT**INT | no |
<< , <<= | left bit-shift | numeric | yes | no | no |
>> , >>= | right bit-shift | numeric | yes | no | no |
& , &= | bit-wise And | numeric | yes | no | no |
| , |= | bit-wise Or | numeric | yes | no | no |
^ , ^= | bit-wise Xor | numeric | yes | no | no |
== | equals to | bool | yes | yes, also integer | yes, also integer |
!= | not equals to | bool | yes | yes, also integer | yes, also integer |
> | greater than | bool | yes | yes, also integer | yes, also integer |
>= | greater than or equals to | bool | yes | yes, also integer | yes, also integer |
< | less than | bool | yes | yes, also integer | yes, also integer |
<= | less than or equals to | bool | yes | yes, also integer | yes, also integer |
.. | exclusive range | range | yes | no | no |
..= | inclusive range | range | yes | no | no |
Examples
let x = (1 + 2) * (6 - 4) / 2; // arithmetic, with parentheses
let reminder = 42 % 10; // modulo
let power = 42 ** 2; // power
let left_shifted = 42 << 3; // left shift
let right_shifted = 42 >> 3; // right shift
let bit_op = 42 | 99; // bit masking
Floating-Point Interoperates with Integers
When one of the operands to a binary arithmetic operator is floating-point, it works with integer for the other operand and the result is floating-point.
let x = 41.0 + 1; // float + integer
type_of(x) == "f64"; // result is float
let x = 21 * 2.0; // float * integer
type_of(x) == "f64";
(x == 42) == true; // float == integer
(10 < x) == true; // integer < float
Decimal Interoperates with Integers
When one of the operands to a binary arithmetic operator is decimal, it works with integer for the other operand and the result is decimal.
let d = parse_decimal("2");
let x = d + 1; // decimal + integer
type_of(x) == "decimal"; // result is decimal
let x = 21 * d; // decimal * integer
type_of(x) == "decimal";
(x == 42) == true; // decimal == integer
(10 < x) == true; // integer < decimal
Unary Before Binary
In Rhai, unary operators take [precedence] over binary operators. This is especially important to
remember when handling operators such as **
which in some languages bind tighter than the unary
-
operator.
-2 + 2 == 0;
-2 - 2 == -4;
-2 * 2 == -4;
-2 / 2 == -1;
-2 % 2 == 0;
-2 ** 2 = 4; // means: (-2) ** 2
// in some languages this means: -(2 ** 2)