DCL

An elegant OOP with mixins + AOP for JavaScript.

dcl.isInstanceOf()

While instanceof operator works only for linear prototypal inheritance, dcl.isInstanceOf() is its counterpart for mixins.

Description

JavaScript provides instanceof operator to check if an object was produced with a certain constructor or its delegate. Unfortunately this functionality works only for a linear delegation. Mixins are by necessity mixed in, so they cannot be detected by instanceof. This functionality is provided by dcl.isInstanceOf() function, which takes an object and a constructor as parameters, and returns a Boolean value.

dcl.isInstanceOf()
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var A = dcl(null, {});
var B = dcl(null, {});
var C = dcl(null, {});
var D = dcl(null, {});

var ABC = dcl([A, B, C], {});
var abc = new ABC();

console.log(abc instanceof A); // true
console.log(abc instanceof B); // false
console.log(abc instanceof C); // false
console.log(abc instanceof D); // false

console.log(dcl.isInstanceof(abc, A)); // true
console.log(dcl.isInstanceof(abc, B)); // true
console.log(dcl.isInstanceof(abc, C)); // true
console.log(dcl.isInstanceof(abc, D)); // false

Notes

This function has a linear complexity on a number of mixins.

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