I've observed this in Firefox-3.5.7/Firebug-1.5.3 and Firefox-3.6.16/Firebug-1.6.2
When I fire up Firebug:
var x = new Array(3)
console.log(x)
// [undefined, undefined, undefined]
var y = [undefined, undefined, undefined]
console.log(y)
// [undefined, undefined, undefined]
console.log(x.constructor == y.constructor) // true
console.log(
x.map(function() { return 0; })
)
// [undefined, undefined, undefined]
console.log(
y.map(function() { return 0; })
)
// [0, 0, 0]
What's going on here? Is this a bug, or am I misunderstanding how to use new Array(3)
?