Operators | Sugar

Arrow syntax

Sugar’s arrows declare three different relationships:

Syntax	Name	Meaning
`value -> "Label"`	Display arrow	Give a Sugar value or declaration a visible label
`name => value`	Mapping arrow	Map a configuration name, match pattern, or random weight to its value or result
`seat var value <- $memory`	Bind arrow	Bind Session seat state to hosted Memory

They are introduced with complete examples in Arrow syntax. They are not interchangeable assignment operators.

Expression	Meaning
`x + y`	Add numbers, concatenate compatible text, or concatenate two lists
`x - y`	Subtract numbers or remove every matching entry in the right list from the left list
`x * y`	Multiply
`x / y`	Divide
`x ^ y`	Raise x to the power y
`x mod y`	Remainder after division

Use parentheses to make evaluation order clear:

(base + bonus) * multiplier

List arithmetic creates a new list without mutating either input:

let combined = common + rare;
let filtered = combined - blocked;

Comparison results are booleans.

Expression	Meaning
`x and y`	True when both values are true
`x or y`	True when at least one value is true
`not x`	Invert a boolean condition

value in list
value not in list

Example:

mood in ("PLAYFUL", "ROMANTIC")

Expression	Values produced
`1..5`	1, 2, 3, 4
`1..=5`	1, 2, 3, 4, 5

Range bounds must be whole numbers and the end cannot be below the start. A range contains at most 100 values.

Ranges are lists, so they work with membership and functions that accept a list:

score in 1..=10
Rand::pick(1..=20)

item.name
item["name"]
rewards[1]
value[key]

List indexes begin at 1. Missing or blocked object properties resolve safely instead of exposing JavaScript prototypes.

:: accesses a function grouped under a Sugar namespace:

Date::now()
Rand::pick(1..=20)
Id::short()

Use :: for a namespace function and . for a value’s property, as in Date::now().weekday.

Assignments require a variable that can be changed in that type of Sugar program.

Nested assignment is supported:

character.stats.health--;

if condition then value else otherValue

This form returns one of two values and does not use braces. Statement-form decisions use brace bodies instead.

Syntax	Meaning
`1 => value`	Match one literal value
`1 \| 2 => value`	Match either pattern
`1..5 => value`	Match 1 through 4
`1..=5 => value`	Match 1 through 5
`("A", _) => value`	Match an exact two-entry list structure
`_ => value`	Match anything not handled earlier

Inside match, the mapping arrow => separates a pattern from its result. The | pattern operator combines patterns in one arm.

Rand::weighted() also uses =>, with a numeric weight on the left and its possible result on the right.