# [racket-dev] Single-flonum-ness not preserved in racket/math functions

I'm currently adding degrees->radians, radians->degrees, exact-round,
exact-floor, exact-ceiling, exact-truncate, nan?, and infinite? to
racket/math. (Along with docs and test cases, of course.)
When I started to add their types to Typed Racket's base environment, I
found that some of the existing function's types didn't match their
behavior. I think it's racket/math's fault, not TR's.
As long as I'm working on racket/math, should I just fix it?
Example:
> (sinh 1.0f0)
- : Single-Flonum [generalized from Positive-Single-Flonum]
1.175201177597046
That's obviously wrong. The fix is simple: change 2.0 in the definition
of sinh to 2.
Vincent, is there a quick way for me to test whether the types I give
the new functions are sound?
A related question: In some timing tests, I've found that wrapping the
definitions in racket/math with begin-encourage-inline made some things
faster; in particular, expressions which, when inlined, would be
constant-lifted. Is there any reason to not add the inline hint?
Neil ⊥