Object Class
Object is Alia's built-in object class, used to store collections of key-value pairs. Alia's object system provides rich property operations and methods.
Creating Objects
Using Literals
const obj1 = *[name: 'Alice', age: 25]
const obj2 = *[
name: 'Bob',
age: 30,
address: *[
city: 'Beijing',
country: 'China'
]
]
Using the Constructor
const seed = *[name: 'Alice']
const obj3 = Object.create seed
const entries = [['name', 'Alice'], ['age', 25]]
const obj4 = Object.fromEntries entries
Importing from a JSON File
Alia supports importing data directly from JSON files via the import statement, automatically converting it to the Object type.
~ Contents of config.json:
~ { "name": "Alice", "age": 30, "isStudent": true, "scores": [95, 88, 92] }
import 'config.json' as config
print Object.get config keyed 'name' ~ outputs 'Alice'
print Object.get config keyed 'age' ~ outputs 30
print Object.get config keyed 'isStudent' ~ outputs true
Features:
- JSON objects are automatically converted to Alia
Objects - JSON arrays are automatically converted to Alia
Arrays - JSON primitive types (strings, numbers, booleans, null) are automatically converted to the corresponding Alia types
- Nested structures are supported
Methods
Property operations on Object are performed uniformly through static method calls, with the object passed in as the first argument.
Object.create
Creates a new object. Takes a single value argument and returns the new object.
const seed = *[name: 'Alice']
const obj = Object.create seed
Object.fromEntries
Creates an object from an array of key-value pairs. Takes a single array argument and returns the new object.
const entries = [['name', 'Alice'], ['age', 25]]
const obj = Object.fromEntries entries
print obj ~ outputs *[name: Alice, age: 25]
Object.assign
Merges multiple objects. Source objects are chained after the target with with; the number of sources is variable, and the merged new object is returned.
const obj1 = *[name: 'Alice']
const obj2 = *[age: 25]
const obj3 = *[city: 'Beijing']
const merged = Object.assign obj1 with obj2 with obj3
print merged ~ outputs *[name: Alice, age: 25, city: Beijing]
Object.keys
Returns the array of property names of the object. Takes a single object argument and returns an array.
const obj = *[name: 'Alice', age: 25]
print Object.keys obj ~ outputs ['name', 'age']
Object.values
Returns the array of property values of the object. Takes a single object argument and returns an array.
const obj = *[name: 'Alice', age: 25]
print Object.values obj ~ outputs ['Alice', 25]
Object.entries
Returns the array of key-value pairs of the object. Takes a single object argument and returns an array.
const obj = *[name: 'Alice', age: 25]
print Object.entries obj ~ outputs [['name', 'Alice'], ['age', 25]]
Object.contact
Merges two objects. The left and right objects are chained with with, and the merged new object is returned.
const obj1 = *[name: 'Alice']
const obj2 = *[age: 25]
const merged = Object.contact obj1 with obj2
print merged ~ outputs *[name: Alice, age: 25]
Object.isObject
Checks whether a value is an Alia object. Takes a single value argument and returns a boolean.
const obj = *[name: 'Alice']
const arr = [1, 2, 3]
print Object.isObject obj ~ outputs true
print Object.isObject arr ~ outputs false
Object.clone
Creates a shallow copy of the object. Takes a single object argument and returns the new object.
const original = *[name: 'Alice', age: 25]
const copy = Object.clone original
print copy ~ outputs *[name: Alice, age: 25]
Object.set
Sets a property on the object. The key is specified with keyed and the value with to; the object passed in is returned as-is.
const obj = *[name: 'Alice']
Object.set obj keyed 'age' to 25
print obj ~ outputs *[name: Alice, age: 25]
Object.get
Gets a property from the object. The key is specified with keyed and the default value with or; when the default value is omitted it is Null. Returns the property value or the default value.
const obj = *[name: 'Alice']
print Object.get obj keyed 'name' ~ outputs 'Alice'
print Object.get obj keyed 'age' or 0 ~ outputs 0
Object.has
Checks whether the object contains the specified property. The key is specified with keyed; returns a boolean.
const obj = *[name: 'Alice', age: 25]
print Object.has obj keyed 'name' ~ outputs true
print Object.has obj keyed 'email' ~ outputs false
Object.delete
Deletes a property from the object. The key is specified with keyed; returns a boolean.
const obj = *[name: 'Alice', age: 25]
Object.delete obj keyed 'age'
print obj ~ outputs *[name: Alice]
Object.toPlain
Converts to a plain value. Takes a single object argument and returns its plain-value representation.
const obj = *[name: 'Alice', age: 25]
print Object.toPlain obj ~ outputs [object Object]
Object.toArray
Converts to an array of key-value pairs. Takes a single object argument and returns an array.
const obj = *[name: 'Alice', age: 25]
print Object.toArray obj ~ outputs [['name', 'Alice'], ['age', 25]]
Printing Objects
Directly outputting an object displays its structural representation:
const obj = *[name: 'Alice', age: 25]
print obj ~ outputs Object *[ String name: "Alice", Number age: 25 ]
Property Access
Access properties using dot syntax:
const obj = *[name: 'Alice', age: 25]
print obj.name ~ outputs 'Alice'
print obj.age ~ outputs 25
Access nested properties using dot syntax:
const obj = *[
user: *[
profile: *[
name: 'Alice'
]
]
]
print obj.user.profile.name ~ outputs 'Alice'
Example Code
~ Comprehensive object example
~ 1. Create an object
const person = *[name: 'Alice', age: 25]
print person
~ 2. Property access
print 'Name: ' .. person.name
print 'Age: ' .. person.age
~ 3. Check a property
if Object.has person keyed 'name' {
print 'Object contains the name property'
}
~ 4. Set a property
Object.set person keyed 'city' to 'Beijing'
print person
~ 5. Get a property (with a default value)
const email = Object.get person keyed 'email' or 'unknown'
print 'Email: ' .. email
~ 6. Delete a property
Object.delete person keyed 'city'
print person
~ 7. Get keys, values, and entries
print ('All keys: ' .. (Object.keys person))
print ('All values: ' .. (Object.values person))
print ('All entries: ' .. (Object.entries person))
~ 8. Clone an object
const copy = Object.clone person
print copy
~ 9. Merge objects
const extra = *[job: 'Developer']
const merged = Object.contact person with extra
print merged
~ 10. Use static methods
const entries = [['a', 1], ['b', 2]]
const fromEntries = Object.fromEntries entries
print fromEntries
const source1 = *[x: 1]
const source2 = *[y: 2]
const source3 = *[z: 3]
const assigned = Object.assign source1 with source2 with source3
print assigned
~ 11. Nested objects
const nested = *[
user: *[
profile: *[
name: 'Bob',
avatar: 'avatar.png'
]
]
]
print 'Nested access: ' .. (nested.user.profile.name)
~ 12. Iterate over an object
const config = *[host: 'localhost', port: 8080, debug: true]
const keys = Object.keys config
for { let i = 0 } i < keys.length { i ++ } {
print (keys[i] .. ': ' .. (Object.get config keyed keys[i]))
}