We now turn our attention to the representation of the Mini-ML typing
judgment in LF. It turns out that the typing judgment is an example of
a so-called hypothetical judgment, where the typing assumptions for the
free variables in an expression are the hypotheses. Since the typing
judgment of LF is also hypothetical, we can take advantage of the
higher-order nature of the framework to give a concise representation of
the Mini-ML typing rules. These rules, when interpreted as an Elf
program, can be used for Mini-ML type inference.