"JavaScript, with its death grip on the Interwebs and every AJAX developer’s language of only choice, is getting hot. With roll-overs, pop-ups, and menus either solved or relegated to CSS behaviors, XMLHttpRequests have made JavaScript once again a language of innovation. This article is meant to offer a tidbit of idiomatic advice for people who know JavaScript or want to know JavaScript coming from Java, C, Python, Perl, or PHP.
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Novice: objects and associative arrays
Novice: cute type conversions
Novice: iteration
Acolyte: anonymous functions
Acolyte: enclosure
Acolyte: context object manipulation
Acolyte: variadic arguments
Guru: binding
Guru: lazy function definition
Guru: polymorphic callable objects
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JavaScript Tips for Novices, Acolytes, and Gurus