Closes#373
This forbids expressions such as `a and b or c`, avoiding the need to set an
implicit priority between `and`, `or` and `xor`, which I find error-prone.
Instead, when that appears, a message asking for explicit parentheses will be
shown to the user.
Implementation note: since that would be extremely tedious to do in the parser
directly, the parser is set to allow right-associativity without discrimination
for the logical operators, and the check is done during desugaring. This
required to explicit parentheses in the surface AST to discriminate the case
where the priority was explicit.
In particular `CONSTRUCTOR` is no longer valid for paths & modules, so let's
switch to the more usual LIDENT / UIDENT for lower- or upper- case idents.
cd compiler/surface
sed -i 's/VERTICAL/BAR/g' *
sed -i 's/BRACKET/BRACE/g' *
sed -i 's/SQUARE/BRACKET/g' *
sed -i 's/IDENT/LIDENT/g' *
sed -i 's/CONSTRUCTOR/UIDENT/g' *
Define a single expression rule with disambiguation using token priorities
instead of the many layers of intermediate rules with explicit sub-terms.
Also replaces `in` for collection operations (`x+1 for foo in [1;2]`) with
`among` which helps a lot.
Overloads are powerful, but let's clearly draw the line right now between
convenience and type safety, for when someone else will want to add new
operators.
When working through the tutorial, I was thrown off a bit by this minor typo. The typo made it look like the tax calculation was subtracting the $10,000 exception from above, as opposed to the $100,000 from the bracket.
it's unlikely to be used in any law, and likely to be cause for confusion.
best of all, the new operator has a different return type, which
ensures no inconsistency with the change can get overlooked.
Command used: `sed -i 's/\([-+*/><=]=\?\)[.$@^€$]/\1/g' **/*/*.catala_*`
The overload test, of course, is kept unchanged and ensures that explicit
operators still work.
This uses the same disambiguation mechanism put in place for
structures, calling the typer on individual rules on the desugared AST
to propagate types, in order to resolve ambiguous operators like `+`
to their strongly typed counterparts (`+!`, `+.`, `+$`, `+@`, `+$`) in
the translation to scopelang.
The patch includes some normalisation of the definition of all the
operators, and classifies them based on their typing policy instead of
their arity. It also adds a little more flexibility:
- a couple new operators, like `-` on date and duration
- optional type annotation on some aggregation constructions
The `Shared_ast` lib is also lightly restructured, with the `Expr`
module split into `Type`, `Operator` and `Expr`.
Some typing errors are changed a little, because they get triggered during the
typing of the disambiguation pass, which does not specify the expected return
type (it's an expected invariant that it should not be needed for
disambiguation).
It would be possible to still specify these types during disambiguation just to
get the same errors, but since the newer ones don't appear to be clearly worse
at the moment, it has not been done.
This is just a bunch of `sed` calls:
```shell
sed -i 's/ScopeSet/ScopeName.Set/g' compiler/**/*.ml*
sed -i 's/ScopeMap/ScopeName.Map/g' compiler/**/*.ml*
sed -i 's/StructMap/StructName.Map/g' compiler/**/*.ml*
sed -i 's/StructSet/StructName.Set/g' compiler/**/*.ml*
sed -i 's/EnumMap/EnumName.Map/g' compiler/**/*.ml*
sed -i 's/EnumSet/EnumName.Set/g' compiler/**/*.ml*
sed -i 's/StructFieldName/StructField/g' compiler/**/*.ml*
sed -i 's/StructFieldMap/StructField.Map/g' compiler/**/*.ml*
sed -i 's/StructFieldSet/StructField.Set/g' compiler/**/*.ml*
sed -i 's/EnumConstructorMap/EnumConstructor.Map/g' compiler/**/*.ml*
sed -i 's/EnumConstructorSet/EnumConstructor.Set/g' compiler/**/*.ml*
sed -i 's/RuleMap/RuleName.Map/g' compiler/**/*.ml*
sed -i 's/RuleSet/RuleName.Set/g' compiler/**/*.ml*
sed -i 's/LabelMap/LabelName.Map/g' compiler/**/*.ml*
sed -i 's/LabelSet/LabelName.Set/g' compiler/**/*.ml*
sed -i 's/ScopeVarMap/ScopeVar.Map/g' compiler/**/*.ml*
sed -i 's/ScopeVarSet/ScopeVar.Set/g' compiler/**/*.ml*
sed -i 's/SubScopeNameMap/SubScopeName.Map/g' compiler/**/*.ml*
sed -i 's/SubScopeNameSet/SubScopeName.Set/g' compiler/**/*.ml*
```
... and reformat
