List out of Lambda

For people who are interested. The theoretical foundations for this is lambda-calculus created by Alonso Church.<p>Encoding integers with lambda is called the curch encoding: <a href="http://en.wikipedia.org/wiki/Church_numerals" rel="nofollow">http://en.wikipedia.org/wiki/Church_numerals</a><p>Functional programming in general is built upon the foundations laid out by him.<p>Actually the domainname of hackernews (ycombinator) has a lot todo with lambda calculus.

<p><pre><code> "If you ignore the practical issues of computers like size, weight, cost, heat, and so on, what do you really need in a programming language?" </code></pre> One instruction<p><a href="https://en.wikipedia.org/wiki/One_instruction_set_computer" rel="nofollow">https://en.wikipedia.org/wiki/One_instruction_set_computer</a>

Turing-completeness, of course. After that, it's all a matter of allowing you to stay as focused as possible on the task at hand: some reasonable way to express your chosen paradigm, library support for things ancillary to your actual task, and some measure of support in the tools you find useful.

It's always cool to see an accessible demo of the lambda calculus, but to nitpick... Isn't it cheating a bit to say this doesn't use Object when, in JavaScript, the persistent <i>arguments</i> object exists and is even explicitly accessible? You're just hiding Object instantiation behind function calls, and using syntactic sugar to access the local object.<p>I'm not totally sold that objects are a "bigger" language feature than closures, conceptually.

It's better to think of map without thinking of looping. I think its a good idea to think of it as converting a container of A to a container of B. It doesn't matter how it happens, and the container might be empty, or only big enough only to hold 1 item. Loop is beside the point.

Seriously, what I need in a programming language depends on what I intend to achieve with it.<p>I use blocks in Objective-C and "closures" in Applescript.<p><pre><code> to lambda(aStatment) script intern say aStatment end script end lambda set a to lambda("applescript…") set b to lambda("knows how to …") set c to lambda("make a closure if not a lambda…") tell a to run tell b to run tell c to run</code></pre>

Solid intro into the lambda calculus. Wasn't so into the js examples, but after reading the other comments, I can totally see how a functional/mathematical syntax would have been very disorienting for someone not familiar with the lambda calc. Since those people are obviously the target audience, js seems fitting.

Having used scheme before, and gone through some of SICP, it was neat to see the topic expressed in JS. I think it came through fine, though I'll always have a love for Scheme!

I'm a bit turned off by the syntax, but lambda calculus is always fun

great read, thanks for sharing.

I get that JavaScript is a popular language, but burying a fundamental concept under a cluttered and confusing syntax like JavaScript, when it's much cleaner to explain the math using sensibly notation.<p>Ugh. It's nice that Steve is reaching down to his audience, but it would be nice for the audience to step out of their muddy sandbox once in a while.