This is neat! Some if the alternative solutions discussed here seem to confuse compilation with evaluation. Fortran is trying to rewrite the computation in such

This is neat! Some if the alternative solutions discussed here seem to confuse compilation with evaluation. Fortran is trying to rewrite the computation in such a way that, later on, a machine that knows nothing about precedence can evaluate the expression. It's incredible that such a rewrite can be performed from left to right without recursion and while using only O(1) memory at a time.