Operators

Arithmetic

Operator	Meaning
+	addition
-	subtraction / unary negation
*	multiplication
/	division
//	floor division
%	modulo
**	exponent (based on the EXPONENT_FUNCTION builtin)

term.log(1 + 2)     # 3
term.log(7 // 2)    # 3
term.log(7 % 2)     # 1

Every arithmetic operator is backed by a global function you can also call directly, and which classes can override by implementing the matching dunder method (e.g. __add__):

term.log(add(1, 2))         # 3
term.log(subtract(5, 2))    # 3
term.log(multiply(2, 3))    # 6
term.log(divide(6, 2))      # 3
term.log(floor_divide(7, 2))# 3
term.log(modulo(7, 2))      # 1
term.log(exponent(2, 3))    # 8

Numeric literals also support scientific notation and hex, e.g. 1e5, 1e7, 0xD800 (see array_set.ar for 1e5 and json/init.ar for hex literals).

Comparison

Operator	Meaning
==	equal
!=	not equal
<	less than
<=	less than or equal
>	greater than
>=	greater than or equal

These also have global function equivalents: equal, not_equal, less_than, less_than_equal, greater_than, greater_than_equal — and each is backed by a dunder method (__equal__, __less_than__, etc.) that a class can override, e.g. the standard number and string types both implement their own comparison dunders.

Logical operators

a && b     # logical AND
a || b     # logical OR   (used in stdlib code, e.g. path.ar's `while ("//" in p)` style checks)
!a         # logical NOT

See my_first_calculator.ar for repeated use of && in condition chains.

The in operator

Test membership in a string, array, or dictionary:

term.log("ell" in "hello")   # true, substring check
term.log(3 in [1,2,3])       # true
term.log("key" in {key: 1})  # true, checks dictionary keys

This is backed by the __contains__ dunder method, which is implemented on strings, arrays, and dictionaries — and can be implemented on your own classes too.

Ternary conditional expression

let result = a < b ? -1 : a > b ? 1 : 0

This is the pattern used in map_filter_sort.ar to write a comparator function in one line.

String concatenation

+ also works on strings:

term.log("hello " + "world")

Ranges

a until b (as seen in range_test.ar) produces an iterable range, most commonly used with for:

for (x in 0 until 1e7) do
    ...

See for loops for more on ranges and the built-in range() function.

Unary operators

-x     # negation
!x     # logical not

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