Can you specify an upper and lower bound for the validity period of a transaction?

Question

I want a transaction to only be valid for a certain period of time relative to some specified start time. I thought that maybe I could use Constraints.mustValidateIn (interval firstInterval $ firstInterval + 10000), but this has failed to validate. It seems that it does not matter what the upper bound is, because it always fails... unless its positive infinity. So this: Constraints.mustValidateIn (from $ firstInterval) always works.

In the docs, Constraints.mustValidateIn has a footnote specifying this: "@mustValidateIn r@ requires the transaction's time range to be contained in @r@."

So I guess what I am asking is what is a transactions time range? And can it be manipulated to fit this scenario?

Thanks!

Answer 1

I discovered this cool function named hull. Here is the function definition from the docs.

-- The function hull gives the smallest interval containing both the given intervals.
hull :: Ord a => Interval a -> Interval a -> Interval a
hull (Interval l1 h1) (Interval l2 h2) = Interval (min l1 l2) (max h1 h2)

I did not expect this to work any better than my previous attempts at specifying some range with an upper limit. But it did.

Here is my constraint now:

Constraints.mustValidateIn (hull (from $ firstInterval)(to $ firstInterval + 8000))