Also slightly extended the check test 'framework' to allow registering side-dependency and using them from another module. This allows to check the interplay between opaque type from within and outside of their host module.
Discard pattern are _dangerous_ is used recklessly. The problem comes
from maintenance and when adding new fields. We usually don't get any
compiler warnings which may lead to missing spots and confusing
behaviors.
So I have, in some cases, inline discard to explicitly list all
fields. That's a bit more cumbersome to write but hopefully will catch
a few things for us in the future.
Before this commit, we would always show the 'declared form' of type aliases, with their generic, non-instantiated parameters. This now tries to unify the annotation with the underlying inferred type to provide even better alias pretty printing.
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.
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.
This was somewhat weirdly done, with a boolean 'imported' set on the
formers; but an explicit new warning for values. I don't see the point
of distinguishing them so I just merged them all into a single
warning.
I have however preserved the 'UnusedType' and 'UnusedConstructor'
warnings since they were ALSO used for unused private constructors or
types.
I initially removed the 'UnkownTypeConstructor' since it wasn't used anywhere and was in fact dead-code. On second thoughts however, it is nicer to provide a slightly better error message when a constructor is missing as well as some valid suggestion. Prior to that commit, we would simply return a 'UnknownVariable' and the hint might suggest lowercase identifiers; which is wrong.
It is now possible to leave a hole in a type annotation and have the compiler fill-in the expected type of us.
This is a pretty useful debugging tool when playing with complex functions.
Before that commit, the type-checker would allow unsafe list patterns
such as:
```
let [x] = xs
when xs is {
[x] -> ...
[x, ..] -> ...
}
```
This is quite unsafe and can lead to confusing situations. Now at
least the compiler warns about this. It isn't perfect though,
especially in the presence of clause guards. But that's a start.
I decided to invert how I'm doing it. I'm passing
in a new argument to unify in environment called
allow_cast: bool and essentially at various
unification sites I can control whether or not I
want to allow casting to even occur. So we can
assume it's false by default always and then we
turn it on in a few places vs. just opening the
flood gates and locking it down at various sites
as they come up# Please enter the commit message
for your changes. Lines starting
* you cannot cast FROM Data with a `let`
* you cannot cast FROM Data by passing
Data to none Data when calling a function
* you MUST use `assert` to cast from data
* you can cast INTO Data with a `let`
* you can cast INTO Data by passing none Data
to Data when calling a function
* You cannot assert cast Data without an
annotation
## Before
```
× Type-checking
╰─▶ Unknown module field 'ValidityRaneg' in module 'aiken/transaction'
```
## After
```
× Type-checking
╰─▶ Unknown import 'ValidityRaneg' from module 'aiken/transaction'
╭─[../stdlib/validators/tmp.ak:2:1]
2 │ use aiken/interval.{Interval, IntervalBound, IntervalBoundType}
3 │ use aiken/transaction.{ScriptContext, ValidityRaneg}
· ─────────────
4 │
╰────
help: Did you mean to import 'ValidityRange'?
```
## Before
```
× Checking
╰─▶ Unexpected labeled argument
t
╭─[/Users/mati/Devel/OpenSource/time_lock_aiken/validators/time_lock.ak:13:1]
13 │ let now = when context.transaction.validity_range.lower_bound.bound_type is {
14 │ Finite { t } -> t
· ─
15 │ NegativeInfinity -> 0
╰────
```
## After
```
× Type-checking
╰─▶ Unexpected labeled argument 't'
╭─[../stdlib/validators/tmp.ak:10:1]
10 │ let now = when context.transaction.validity_range.lower_bound.bound_type is {
11 │ interval.Finite { t } -> t
· ─
12 │ interval.NegativeInfinity -> 0
╰────
help: The constructor 'Finite' does not have any labeled field. Its fields
must therefore be matched only by position.
Perhaps, try the following:
╰─▶ interval.Finite(t)
```