How to execute "eval" without writing "eval" in JavaScript

Not sure if I understood you, but you can apply a function to a specific local (this) scope:

var x = 5;

var f = new Function('alert(this.x)');

function A(x){
    this.x = x;
    f.apply(this,[]);
}

a = new A(10);

This alerts 10 as f is applied with A.this

Thanks for all the ideas, I ended up just doing text replacement in the build script that outputs the JS, basically replacing $EVAL$ with eval, after everything has been compressed. I was hoping for a purely JS way, but with so many different eval browser implementations, it's probably better to just leave eval alone

But based on Dimitar's answer and some fiddling around, here's what I found. Seems like the reason why this['eval'] wasn't work is because the place where it's happening, in MooTools JSON.decode, is also a inside a Hash:

var JSON = new Hash({
  // snip snip
  decode: function(string, secure) {
    if ($type(string) != 'string' || !string.length) return null;
    if (secure && !(/^[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/).test(string.replace(/\\./g, '@').replace(/"[^"\\\n\r]*"/g, ''))) return null;

    return this.eval('(' + string + ')'); // Firefox says: TypeError: this.eval is not a function
  }
});

However, if I store the "top level" local scope (all the code, including mootools, runs inside an anonymous function), then it works:

var TOP = this;
var JSON = new Hash({
  // snip snip
  decode: function(string, secure) {
    if ($type(string) != 'string' || !string.length) return null;
    if (secure && !(/^[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/).test(string.replace(/\\./g, '@').replace(/"[^"\\\n\r]*"/g, ''))) return null;

    return TOP.eval('(' + string + ')'); // All good, things run within the desired scope.
  }
});

However this doesn't work in Safari, so bottom line is, what I was trying to do can't be done cross-compatibly. eval is a special touchy function and every browser treats it differently.