Condensing a sparse array in Javascript?
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I have an array of elements where the entries are sparse.  How can I easily condense the sparse array into a dense array so that I don't have to keep checking for null and undefined values every time I loop through the data?

Here is some example data:

    var sparse = [];
    sparse[1] = undefined;
    sparse[5] = 3;
    sparse[10] = null;
    
    var dense = sparseToDenseArray(sparse);
    // dense should be [3]

