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.
The difference between 'FlexBreak' and 'Break(Mode::Strict/Flexible)' as always confused me; and turned out that the 'FlexBreak' thingy is never used. This is dead-code, so I removed it.
Rules are now as follows:
- If a pipeline contains a newline, then the entire pipeline is formatted over multiple lines.
- If it doesn't, then it's formatted as a single-line UNLESS it cannot fit; in which case, we fallback to multiline again.
This was a bit tricky and I ended up breaking things down a lot and
trying different path. This commit is the result of the most
satisfying one.
It introduces a new 'concept' and types: Definitions and Reference.
These elements are meant to reflect JSON pointers and JSON-schema
definitions which we now use for pretty much all user-defined
data-types.
In fact, Schemas are no longer inlined, but are always referencing
some schema under "definitions".
This indirection is necessary in order to cope with recursive types.
And while it's only truly necessary for recursive types, using it
consistently makes it both easier to produce and easier to consume.
---
The blueprint generation for recursive types here also works thanks to
the 'Definitions' data-structure wrapper around a BTreeMap. This uses
a strategy where:
(1) schemas are only generated if they haven't been seen before
(2) schemas are marked as seen BEFORE actually being generated (to
effectively stop a recursive generation).
This relies on one important aspect: the key must be uniquely
identifying a given schema. Which means that we have to monomorphize
data-types with generic parameters also here, and use keys that are
specialized in one data-type.
---
In this large overhaul we've also lost one thing which I didn't bother
re-introducing yet to keep the work manageable: title for record
fields. Before, we use to pull those from record constructor when
available, yet now, every record constructor has been replaced by a
`$ref`. We could theoritically attach a title to the reference. I'll
try to quickly add that in a later commit.
-> The provided Plutus code called 'error'.
This scenario _could_ work if `choose_data` was lazy in its arguments.
Which is a reasonable thing to expect from `choose_data`. Since we
don't have any way to introduce on-demand lazyness in the language
(and we are not looking for ways), we need to make a special case for
`choose_data` which is a perfect (and singular) use case for it.