Rimu expressions
Expression
Value
The simplest expression is a Value literal.
Identifier
Identifiers must conform to regex:
^[a-zA-Z_][a-zA-Z0-9_]*$
hello
Unary operator
Operand must be a number.
- (negate)
-10
! (not)
Operand must be a boolean.
!is_done
Binary Operator
+ (add)
Operands must be numbers, strings, or lists.
10 + 2
"hello" + "world"
[1, 2] + [3, 4]
- (subtract)
Operands must be numbers.
10 - 2
* (multiply)
Operands must be numbers.
10 * 2
/ (divide)
Operands must be numbers.
10 / 2
> (greater than)
10 / 2
>= (greater than or equal)
10 >= 2
< (less than)
10 < 2
<= (less than or equal)
10 <= 2
== (equal)
10 == 2
!= (not equal)
10 == 2
&& (and)
10 == 2
|| (or)
10 == 2
^ (xor)
Operands must be booleans.
true ^ false
% (remainder)
Operands must be numbers.
10 == 2
Call
Value being called must be a function.
add(1, 2)
Get Index
Container must be list or string or object.
list[2]
list[-2]
string[2]
object["a"]
Get Key
Container must be object
object.a
Get Slice
Container must be list or string.
list[2:5]
string[2:5]
Notes
Truthiness
Everything is truthy except false and null.
Orderedness
Only numbers are ordered.
No statements
Every expression is evaluated to a value.
No type coercion
No implicit type coercions.
For example, the following is an error:
2 + "pies"