JSFuck

Common card · No. 485413

JSFuck is an esoteric subset of JavaScript, where code is written using only six characters: [, ], (, ), !, and +. The name is derived from Brainfuck, an esoteric programming language that also uses a minimalistic alphabet of only punctuation. Unlike Brainfuck, which requires its own compiler or interpreter, JSFuck is valid JavaScript code, meaning that JSFuck programs can be run in any web browser or engine that interprets JavaScript. JSFuck is able to recreate all JavaScript functionality using such a limited set of characters because JavaScript allows the evaluation of any expression as any type.

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