mem

$mol_mem

Single-value properties

Properties of a the same values, in terminology of mol is polymorphic methods with the following type of interface:

myProperty< Value >() : Value // getter
myProperty< Value >( next? : Value ) : Value // getter/setter
myProperty< Value >( next? : Value , force? : $mol_mem_force ) : Value // getter/setter with force support

The example of declaring a not cached property:

/// getter
userName() { return 'jin' }

/// getter/setter
userName( next? : string ) {

	if( next === void 0 ) { // check for undefined for switch between getter and setter
		return localStorage.getItem( 'name' ) // pull value
	} else {
		localStorage.setItem( 'name' , next ) // put value
		return next // return next value
	}
}

Examples of usage:

// Set user name 'jin'
userName( 'jin' )

// Get user name 'jin'
userName()

To do a property is cached it is enough to use decorator $mol_mem, which uses under the hood $mol_atom for automatic invalidation of cache:

/// getter
@ $mol_mem
userName() { return $mol_state_local.value( 'name' ) }

/// getter/setter
@ $mol_mem
userName( next? : string ) {
	if( next === void ) { // check for undefined for switch between getter and setter
		return $mol_state_local.value( 'name' ) // pull value
	} else {
		$mol_state_local.value( 'name' , next ) // put value 
		return next // return next value
	}
}

/// Delegated getter/setter
@ $mol_mem
userName( next? : string ) {
	return $mol_state_local.value( 'name' , next )
}

Additional examples of usage reactive properties:

@ $mol_mem
userName( next? : string , force? : $mol_mem_force ) { // Added force support
	return 'mary'
}

/// Try to set new value
userName( 'jin' ) // returns 'mary'

/// Force push value to cache 
userName( 'jin' , $mol_mem_force_cache ) // returns 'jin'

/// Force cache ignoring and pulling fresh value
userName( void 0 , $mol_mem_force_update ) // returns 'mary'

Multi-value properties

Multi-value properties has the following interface:

myProperty< Key , Value >( key : Key ) : Value // getter
myProperty< Key , Value >( key : Key , next? : Value ) : Value // getter/setter
myProperty< Key , Value >( key : Key , next? : Value , force? : $mol_mem_force ) : Value // getter/setter with force support

$mol_mem_key uses $mol_dict inside.

Examples of declarations:

userName( pos : number ) {
	return `User #${pos}` // value based on key
}

@ $mol_mem_key
userNames( pos : number , next? : string ) {
	return $mol_state_local.value( 'name' , next ) || `User #${pos}`
}

Examples of usages:

/// Set user#0 name to 'jin'
userName( 0 , 'jin' )

/// Get user#0 name 'jin'
userName( 0 )

As a key it is allowed to use any value, which can be serialized into JSON, for example:

@ $mol_mem_key
usersSearch( query : {
	name? : string
	minAge? : number
} ) {
	var users = this.users()
	if( query.name ) users = users.filter( ({ name })=> !!name.match( query.name ) )
	if( query.minAge ) users = users.filter( ({ age })=> age > query.minAge )
	return users
}

adults() {
	return this.usersSearch({ minAge : 18 })
}
jins() {
	return this.usersSearch({ name : 'jin' })
}

Articles

• $mol_atom: теория и практика реактивности - Object oriented reactive programming
• Объектное Реактивное Программирование - Features of Object Reactive Programming