Define Memoized Property
Define a memoized object property.
Usage
var defineMemoizedProperty = require( '@stdlib/utils/define-memoized-property' );
defineMemoizedProperty( obj, prop, descriptor )
Defines a memoized object property.
var obj = {};
function foo() {
return 'bar';
}
defineMemoizedProperty( obj, 'foo', {
'configurable': false,
'enumerable': true,
'writable': false,
'value': foo
});
var v = obj.foo;
// returns 'bar'
A property descriptor has the following required properties:
- value: synchronous function whose return value will be memoized and set as the property value.
A property descriptor has the following optional properties:
- configurable:
booleanindicating if property descriptor can be changed and if the property can be deleted from the provided object. Default:false. - enumerable:
booleanindicating if the property shows up when enumerating object properties. Default:false. - writable:
booleanindicating if the value associated with the property can be changed with an assignment operator. Default:false.
Notes
- Until deferred evaluation, an object property is configurable.
Examples
var fibonacci = require( '@stdlib/math/base/special/fibonacci' );
var defineMemoizedProperty = require( '@stdlib/utils/define-memoized-property' );
function Foo() {
var self;
if ( !(this instanceof Foo) ) {
return new Foo();
}
self = this;
this.count = 0;
defineMemoizedProperty( this, 'fibo', {
'value': fibo
});
return this;
function fibo() {
self.count += 1;
return fibonacci( 73 );
}
}
var foo = new Foo();
var i;
for ( i = 0; i < 10; i++ ) {
console.log( 'F: %d. Count: %d.', foo.fibo, foo.count );
}