Objects

Objects function much like JavaScript objects in the sense that they are just a collection of key-value pairs, where the keys are always strings, and the values can be anything. Like tables in Lua, the keys of an object are not guaranteed to be in any order, and setting a value in an object to null deletes it from the object. However, objects differ from Lua tables in two major ways: 1. The keys are always strings. If you use a key that is not a string, it will be cast to one using Paisley’s type-casting rules. 2. You cannot mix array and object construction syntax; it’s either one or the other. (e.g. {"a" => 123, "b"} is not allowed!)

To define an object, use the arrow operator => between two values, such as "key" => 123 or var => 123. Like with arrays, key-value pairs are allowed to have an optional trailing comma.

let object = {
    'name' => 'Jerry',
    'age' => 30,
    'friend' => (
        'name' => 'Susan',
        'age' => 35,
    ),
}

To create an empty object, just use the arrow operator by itself.

let object = {=>}
let array_of_empties = {
    (=>),
    (=>),
    (=>),
}

Object values can of course be accessed the same way array values can, with the regular indexing [] syntax. However, attributes can also be accessed with dot notation if they contain only alphanumeric characters (that is, they match the pattern [a-zA-Z_][0-9a-zA-Z_]*). The following lines do the exact same thing.

print {object['name']}
print {object.name}

Like with arrays, object values can be added or changed with the following syntax,

let object{'name'} = 'Jekyll'
let object{'friend', 'name'} = 'Hyde'

However, you cannot use the append syntax on an object, as it does not make sense in that context. So the following will not work:

let object{} = 'some value'

Truthiness

If an object contains any values, it is truthy. Empty objects are falsey.

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