Pairwise Differences in CVX

If I want CVX to give me the pairwise differences of the elements of a vector X, what is the most efficient way to do so? In standard MATLAB I would normally use bsxfun(@minus, X, X'), but CVX objects do not support bsxfun).

If X is a column vector, this will work:

X*ones(size(X))' - ones(size(X))*X'