JavaScript Magic Tricks: Fancy Assignment

JavaScript Magic Tricks: Fancy Assignment
Today, let's do a test to see how many different ways there are to write simple JavaScript assignment statements. Here are the test statements, only three lines:

var a=1; a=2; console.log(a); 

For the assignment statement a = 2 in the second line, let's see how many different forms we can transform it into. The first variation is to write it inside an IIFE (Immediately Invoked Function Expression):

var a=1; (function(){ a=2; })(); console.log(a); 

The second variation is to use eval to execute the assignment statement:

var a=1; eval(a=2); console.log(a); 

These two variations are relatively basic and can be easily understood by beginning programmers. Now let's increase the difficulty a bit. The third variation is using evaluated assignment statement with transformations:

var a=1; var b=["a","=",2]; eval(b[0]+b[1]+b[2]); console.log(a); 

But it seems that eval can only be played at this level. Let's show some more difficult variations next.
The fourth variation is to use constructor functions:

var a=1; [].constructor.constructor(a=2); console.log(a); 

Or:

var a=1; [].constructor.constructor(a=2)(); console.log(a); 

The fifth change, the upgrade of constructor function:

var a=1; var b=["a","=",2]; [].constructor.constructor(b[0]+b[1]+b[2])(); console.log(a); 

As with the change in the content of eval, the code executed on the structure is also transformed using the splicing of array content:

The sixth variation, deformation of constructor function:

var a=1; var b=["a","=",2,"constructor"]; [][b[3]][b[3]](b[0]+b[1]+b[2])(); console.log(a); 

The seventh variation, obfuscation and encryption: Using JShaman JavaScript Obfuscator to obfuscate above code.

var a=0x2c0f8^0x2c0f9; var b=['a','=',0xe3b2c^0xe3b2e,'constructor']; [][b[0xa8ddf^0xa8ddc]][b[0xb3a35^0xb3a36]](b[0x3333f^0x3333f]+b[0x84d18^0x84d19]+b[0x50958^0x5095a])(); console['log'](a); 

The resulting code completely obscures the assignment operation of a=2.