How to use Math.max, etc. as higher-order functions
In short, this works:
[1, 2, 3].reduce(function (a, b) { return Math.max(a, b); });
=> 3
But this doesn't:开发者_如何学C
[1, 2, 3].reduce(Math.max);
=> NaN
Pure puzzlement.
This is in Firefox 3.5.9, which I presume is using the mozilla standard implementation of reduce, FWIW.
Math.max
can be used as a higher-order function. The problem is .reduce
will call the function with 4 arguments:
Math.max(accumulator, value, index, the_array)
here is the_array
is an array, so Math.max
returns NaN. I don't think there's simpler way to discard the last 2 arguments.
Math.max.apply(Math, [1, 2, 3]);
//3
Not exactly a higher order use, but this also works:
Math.max(...myArray);
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