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A JavaScript "eval is evil" narrative by way of the "pass a string to setTimeout" anti-pattern...
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// An object with a property and a method. | |
var obj = { | |
name: "Ben", | |
logName: function() { | |
console.log(this.name); | |
} | |
}; | |
// And another global variable, for good measure. | |
var name = "Whoops"; | |
// Even though this works great... | |
obj.logName(); // logs "Ben" | |
// This doesn't, because of how JavaScript determines the "this" value... | |
setTimeout(obj.logName, 1000); // logs "Whoops" in one second. | |
// Someone who doesn't really understand JavaScript might fall back on eval... | |
setTimeout("obj.logName();", 1000); // logs "Ben" in one second. | |
// When they should instead be either doing this... | |
setTimeout(function() { | |
obj.logName(); | |
}, 1000); // logs "Ben" in one second. | |
// Or, in environments that support ES5, this. | |
setTimeout(obj.logName.bind(obj), 1000); // logs "Ben" in one second. |
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