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Comment by cbsmith | Hacker News Reader

Also I hear that JavaScript thing is catching on...

JavaScript is Lisp now?

It's pretty damn close. First class functions give javascript great power. Combined with something like sweet.js and underscore, and javascript becomes a language with the functional library of a lisp along with macros. After that, javascript is just lisp with really weird syntax.

Not to be snarky, but that's like saying 'Javascript is just a Lisp except without the only characteristic that defines a Lisp'.

All the dialects of Lisp differ except in their homoiconicity, which is the one thing that gives Lisps their incredible expressive power.

I get frustrated when I hear people refer to languages with first-class functions as Lisp-like, because lots of languages have first-class functions, but that doesn't give them the power of Lisp - Lisp draws its power from homoiconic structure, which almost no other languages have (certainly not Javascript).

Most of my comment comes from the fact that Eich originally wanted to build a homoiconic lisp for netscape and built many of the features into javascript instead. Still no a lisp ,but it was designed to be similar. http://www.2ality.com/2011/03/javascript-how-it-all-began.ht...

Crockford called it "Lisp in C's Clothing" and then created this: http://www.crockford.com/javascript/little.html

I like the comparisons with ClojureScript: http://himera.herokuapp.com/synonym.html The major thing that continues to really annoy me about JS is the lack of proper lexical scoping, other deficiencies are just slight annoyances now (especially with a couple libraries that help the language be tolerable in certain use cases--e.g. https://github.com/coolaj86/futures).

JS has no "proper lexical scoping"? How so? I'm really curious... what your definition of "proper" is here, because JS definitely has lexical scoping.

Paste this into your browser location bar (it won't navigate away):

    javascript:void(function(){a = 1; {var a = 2;} alert(a)}())

That var a doesn't declare a new var within its scope, it declares it in the function, plus it is counterintuitive how that var a "retroactively" makes that local scope. Javascript has lexical scoping, but only within functions, not within all the scopes other languages have.

You want block scoping. Block scoping is coming in ES6 with the let keyword.

Python is the same here, for example, any many other languages too. Making `a` a local variable here is rather ugly thing to do, but it's (somewhat) consistent with how `function` keyword (not an expression) works.

The point being: JS implements full and proper lexical scoping; implementing lexical scoping for every block is not a requirement for having lexical scoping.

> "Lisp in C's Clothing"

And Perl probably has an even greater claim to this because it shares 6 of the 7 What Makes Lisp Different? things described by Norvig.

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