Version 1.x

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.

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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.