Self-referencing Keys in JavaScript Object Declarations

Tue, 21 Mar 2017 00:00:00 +0800

Often times while programming in JavaScript, which I have been doing a lot lately, I find myself wanting to refer to a key that I have just declared when I am initializing an object.

const myNewObj = {
 a: 'xxx',
 b: 'yyy',
 c: a + this.b, // doesn't work
};

console.log(myNewObj.c); // undefined

Here, neither a or this.b would work since there is no a yet while c is being defined and this does not refer to myNewObj. Obviously, you could define xxx and yyy in separate variables first and refer to them later in the object initialization. Or you could initialize the object without c key and later define c as myNewObj.c = myNewObj.a + myNewObj.b;. But a neater way that I found out is to utilize getters.

Finding A Knight's Tour

Fri, 12 Feb 2016 00:00:00 +0800

A Knight’s Tour is a sequence of moves done by a knight on a chessboard such that it visits each and every square exactly once. Subsequently, the objective of the Knight’s Tour problem is to determine whether there exists a Knight’s Tour from a given starting position. In graph theory terms, it is a form of Hamiltonian path where you visit each vertex of the graph exactly once along the path. Tours can also be cyclic or closed if the final square is a knight’s move away from the first and acyclic or open otherwise.

Programming on khz

Self-referencing Keys in JavaScript Object Declarations

Finding A Knight's Tour