mlton usage messages

[Stephen Weeks]

> I like the MLton usage message.  Is the default always listed first?

Yes, for booleans.

> If I use -v2, does it still fit (79 columns max)?

-v2 and -v3 are the same as -v.

> I guess I would have included -detect-overflow as a non-compiler-hacker flag.

It is.  The first message was for normal users.  The second was for compiler
hackers.

> Also, you didn't include Int.div and Int.quot, which can overflow in the most
> negative over -1 case.

Hmm, the mail I sent said

    -detect-overflow {true|false} overflow checking on integer arithmetic

which I now see is misleading, since at least for now detect-overflow only
covers Int.{+,-,*}.  There are other overflow checks done in the basis library
code for things like div and quot.  I should either change the message back to
saying "Int.{+,-,*}" instead of integer arithmetic or the basis library should
be updated to take the -detect-overflow flag into account.