JSON and JSONP

(extractos en espaƱol)

There’s been an interesting discussion over at JSMentors.com about JSONP and how to make it safer. This is a good thing, not least because it forced me to take a deeper look and come up with a (sort of) counter-proposal of my own.

We’ll start with an overview of JSON basics, including the EcmaScript 5 JSON API, and then discuss cross-domain JSON retrieval via JSONP. Finally I’ll introduce a simple and relatively safe JSONP framework and show how to use it to fetch tweets from the Twitter database.

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How evil is eval?

“eval is Evil: The eval function is the most misused feature of JavaScript. Avoid it”

Douglas Crockford in JavaScript: The Good Parts

I like The Good Parts. It’s essential reading for anyone who’s serious about JavaScript – and I realize that Crockford’s goal here is to emphasize only what he likes – but still I think that such a brief yet total rejection might send the wrong message.

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