The parameter is special as it takes no annotation but a 'via' keyword followed by an expression that should unify to a Fuzzer<a>, where Fuzzer<a> = fn(Seed) -> (Seed, a). The current commit only allow name identifiers for now. Ultimately, this may allow full expressions.
We cannot enforce internal invariants on opaque types from only structural checks on Data. Thus, it is forbidden to find an opaque type in an outward-facing interface. Instead, users should rely on intermediate representations and lift them into opaque types using constructors and methods provided by the type (e.g. Dict.from_list, Rational.from_int, Rational.new, ...)
We've been wrongly representing large ints as BigInt, causing them to
behave differently in the VM through builtins like 'serialise_data'.
Indeed, we expect anything that fits in 8 bytes to be encoded as Major
Type 0 or 1. But we were switching to encoding as Major type 6
(tagged, PosBigInt, NegBigInt) for much smaller values! Anything
outside of the range [-2^32, 2^32-1] would be treated as big int
(positive or negative).
Why? Because we checked whether a value i would fit in an i64, and if
it didn't we treated it as big int. But the reality is more subtle...
Fortunately, Rust has i128 and the minicbor library implements TryFrom
which enforces that the value fits in a range of [-2^64, 2^64 - 1], so
we're back on track easily.
While looking at some code, I noticed that this
warning would show up even if an error for a
non-exhaustive when/is shows up for the same when/is
expression. This isn't a useful situation to show this
warning because things are not exhaustive yet so we should
let the user finish and only provide the errors. If things
are exhaustive then the code proceeds and if a warning was set
when there's only one clause pattern then this warning message
can be pushed because that's when it's actually useful.
This commit allows Data to be optionally annotated with a
phantom-type. This doesn't change anything in codegen but we can now
leverage this information to generate better blueprint schemas.
KtorZ