Merge pull request #7454 from roc-lang/ayaz/error-on-invalid-generalized-types

Restrict usages of type variables in non-generalized contexts
This commit is contained in:
Luke Boswell 2025-01-20 11:30:52 +11:00 committed by GitHub
commit c8467b1fe0
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
23 changed files with 273 additions and 182 deletions

View file

@ -532,7 +532,7 @@ pi = 3.14159265358979323846264338327950288419716939937510
## Circle constant (τ)
tau : Frac *
tau = 2 * pi
tau = 6.2831853071795864769252867665590057683943387987502
# ------- Functions
## Convert a number to a [Str].

View file

@ -915,7 +915,7 @@ pub struct DefTypes {
pub loc_symbols: Slice<(Symbol, Region)>,
}
#[derive(Debug, Clone, Copy)]
#[derive(Debug, Clone, Copy, PartialEq)]
pub struct Generalizable(pub bool);
#[derive(Debug, Clone)]

View file

@ -95,22 +95,6 @@ flags! {
/// Prints all type variables entered for fixpoint-fixing.
ROC_PRINT_FIXPOINT_FIXING
/// Verifies that after let-generalization of a def, any rigid variables in the type annotation
/// of the def are indeed generalized.
///
/// Note that rigids need not always be generalized in a def. For example, they may be
/// constrained by a type from a lower rank, as `b` is in the following def:
///
/// F a : { foo : a }
/// foo = \arg ->
/// x : F b
/// x = arg
/// x.foo
///
/// Instead, this flag is useful for checking that in general, introduction is correct, when
/// chainging how defs are constrained.
ROC_VERIFY_RIGID_LET_GENERALIZED
/// Verifies that an `occurs` check indeed only contains non-recursive types that need to be
/// fixed-up with one new recursion variable.
///

View file

@ -1522,18 +1522,18 @@ mod test_reporting {
from_annotation_if,
indoc!(
r"
x : Num.Int *
x : Num.Int _
x = if Bool.true then 3.14 else 4
x
"
),
@r"
@r###"
TYPE MISMATCH in /code/proj/Main.roc
Something is off with the `then` branch of this `if` expression:
4 x : Num.Int *
4 x : Num.Int _
5 x = if Bool.true then 3.14 else 4
^^^^
@ -1547,14 +1547,14 @@ mod test_reporting {
Tip: You can convert between integers and fractions using functions
like `Num.to_frac` and `Num.round`.
"
"###
);
test_report!(
from_annotation_when,
indoc!(
r"
x : Num.Int *
x : Num.Int _
x =
when True is
_ -> 3.14
@ -1562,12 +1562,12 @@ mod test_reporting {
x
"
),
@r"
@r###"
TYPE MISMATCH in /code/proj/Main.roc
Something is off with the body of the `x` definition:
4 x : Num.Int *
4 x : Num.Int _
5 x =
6> when True is
7> _ -> 3.14
@ -1582,7 +1582,7 @@ mod test_reporting {
Tip: You can convert between integers and fractions using functions
like `Num.to_frac` and `Num.round`.
"
"###
);
test_report!(
@ -1910,7 +1910,7 @@ mod test_reporting {
from_annotation_complex_pattern,
indoc!(
r"
{ x } : { x : Num.Int * }
{ x } : { x : Num.Int _ }
{ x } = { x: 4.0 }
x
@ -1921,7 +1921,7 @@ mod test_reporting {
Something is off with the body of this definition:
4 { x } : { x : Num.Int * }
4 { x } : { x : Num.Int _ }
5 { x } = { x: 4.0 }
^^^^^^^^^^
@ -2047,18 +2047,18 @@ mod test_reporting {
missing_fields,
indoc!(
r"
x : { a : Num.Int *, b : Num.Frac *, c : Str }
x : { a : Num.Int _, b : Num.Frac _, c : Str }
x = { b: 4.0 }
x
"
),
@r"
@r###"
TYPE MISMATCH in /code/proj/Main.roc
Something is off with the body of the `x` definition:
4 x : { a : Num.Int *, b : Num.Frac *, c : Str }
4 x : { a : Num.Int _, b : Num.Frac _, c : Str }
5 x = { b: 4.0 }
^^^^^^^^^^
@ -2075,7 +2075,7 @@ mod test_reporting {
}
Tip: Looks like the c and a fields are missing.
"
"###
);
// this previously reported the message below, not sure which is better
@ -3448,7 +3448,7 @@ mod test_reporting {
x : AList Num.I64 Num.I64
x = ACons 0 (BCons 1 (ACons "foo" BNil ))
y : BList a a
y : BList _ _
y = BNil
{ x, y }
@ -4189,9 +4189,8 @@ mod test_reporting {
RBTree k v : [Node NodeColor k v (RBTree k v) (RBTree k v), Empty]
# Create an empty dictionary.
empty : RBTree k v
empty =
Empty
empty : {} -> RBTree k v
empty = \{} -> Empty
empty
"
@ -11218,10 +11217,10 @@ All branches in an `if` must have the same type!
import Decode exposing [decoder]
main =
my_decoder : Decoder (a -> a) fmt where fmt implements DecoderFormatting
my_decoder = decoder
my_decoder : Decoder (_ -> _) _
my_decoder = decoder
main =
my_decoder
"#
),
@ -11230,12 +11229,12 @@ All branches in an `if` must have the same type!
This expression has a type that does not implement the abilities it's expected to:
7 my_decoder = decoder
^^^^^^^
6 my_decoder = decoder
^^^^^^^
I can't generate an implementation of the `Decoding` ability for
a -> a
* -> *
Note: `Decoding` cannot be generated for functions.
"
@ -11251,10 +11250,10 @@ All branches in an `if` must have the same type!
A := {}
main =
my_decoder : Decoder {x : A} fmt where fmt implements DecoderFormatting
my_decoder = decoder
my_decoder : Decoder {x : A} _
my_decoder = decoder
main =
my_decoder
"#
),
@ -11263,8 +11262,8 @@ All branches in an `if` must have the same type!
This expression has a type that does not implement the abilities it's expected to:
9 my_decoder = decoder
^^^^^^^
8 my_decoder = decoder
^^^^^^^
I can't generate an implementation of the `Decoding` ability for
@ -11514,11 +11513,10 @@ All branches in an `if` must have the same type!
import Decode exposing [decoder]
main =
my_decoder : Decoder {x : Str, y ? Str} fmt where fmt implements DecoderFormatting
my_decoder = decoder
my_decoder : Decoder {x : Str, y ? Str} _
my_decoder = decoder
my_decoder
main = my_decoder
"#
),
@r"
@ -11526,8 +11524,8 @@ All branches in an `if` must have the same type!
This expression has a type that does not implement the abilities it's expected to:
7 my_decoder = decoder
^^^^^^^
6 my_decoder = decoder
^^^^^^^
I can't generate an implementation of the `Decoding` ability for
@ -14111,11 +14109,10 @@ All branches in an `if` must have the same type!
import Decode exposing [decoder]
main =
my_decoder : Decoder (U32, Str) fmt where fmt implements DecoderFormatting
my_decoder = decoder
my_decoder : Decoder (U32, Str) _
my_decoder = decoder
my_decoder
main = my_decoder
"#
)
);
@ -14128,11 +14125,10 @@ All branches in an `if` must have the same type!
import Decode exposing [decoder]
main =
my_decoder : Decoder (U32, {} -> {}) fmt where fmt implements DecoderFormatting
my_decoder = decoder
my_decoder : Decoder (U32, {} -> {}) _
my_decoder = decoder
my_decoder
main = my_decoder
"#
),
@r"
@ -14140,8 +14136,8 @@ All branches in an `if` must have the same type!
This expression has a type that does not implement the abilities it's expected to:
7 my_decoder = decoder
^^^^^^^
6 my_decoder = decoder
^^^^^^^
I can't generate an implementation of the `Decoding` ability for
@ -15997,4 +15993,66 @@ All branches in an `if` must have the same type!
Str -> {}
"#
);
test_report!(
invalid_generic_literal,
indoc!(
r#"
module [v]
v : *
v = 1
"#
),
@r###"
TYPE MISMATCH in /code/proj/Main.roc
Something is off with the body of the `v` definition:
3 v : *
4 v = 1
^
The body is a number of type:
Num *
But the type annotation on `v` says it should be:
*
Tip: The type annotation uses the type variable `*` to say that this
definition can produce any type of value. But in the body I see that
it will only produce a `Num` value of a single specific type. Maybe
change the type annotation to be more specific? Maybe change the code
to be more general?
"###
);
test_report!(
invalid_generic_literal_list,
indoc!(
r#"
module [v]
v : List *
v = []
"#
),
@r###"
TYPE VARIABLE IS NOT GENERIC in /code/proj/Main.roc
This type variable has a single type:
3 v : List *
^
Type variables tell me that they can be used with any type, but they
can only be used with functions. All other values have exactly one
type.
Hint: If you would like the type to be inferred for you, use an
underscore _ instead.
"###
);
}

View file

@ -24,7 +24,7 @@ succeed = \x -> Identity(x)
with_default = Res.with_default
yay : Res.Res {} err
yay : Res.Res {} _
yay =
ok = Ok("foo")

View file

@ -24,7 +24,7 @@ succeed = \x -> Identity(x)
with_default = Res.with_default
yay : Res.Res {} err
yay : Res.Res {} _
yay =
ok = Ok("foo")

View file

@ -271,11 +271,13 @@ fn load_fixture(
);
}
assert!(loaded_module
.type_problems
.remove(&home)
.unwrap_or_default()
.is_empty());
assert_eq!(
loaded_module
.type_problems
.remove(&home)
.unwrap_or_default(),
Vec::new()
);
let expected_name = loaded_module
.interns
@ -433,11 +435,13 @@ fn module_with_deps() {
loaded_module.can_problems.remove(&home).unwrap_or_default(),
Vec::new()
);
assert!(loaded_module
.type_problems
.remove(&home)
.unwrap_or_default()
.is_empty(),);
assert_eq!(
loaded_module
.type_problems
.remove(&home)
.unwrap_or_default(),
Vec::new()
);
let mut def_count = 0;
let declarations = loaded_module.declarations_by_id.remove(&home).unwrap();

View file

@ -105,7 +105,8 @@ pub fn remove_module_param_arguments(
| TypeError::ExpectedEffectful(_, _)
| TypeError::UnsuffixedEffectfulFunction(_, _)
| TypeError::SuffixedPureFunction(_, _)
| TypeError::InvalidTryTarget(_, _, _) => {}
| TypeError::InvalidTryTarget(_, _, _)
| TypeError::TypeIsNotGeneralized(..) => {}
}
}
}
@ -213,6 +214,7 @@ fn drop_last_argument(err_type: &mut ErrorType) {
| ErrorType::Alias(_, _, _, _)
| ErrorType::Range(_)
| ErrorType::Error
| ErrorType::EffectfulFunc => {}
| ErrorType::EffectfulFunc
| ErrorType::InferenceVar => {}
}
}

View file

@ -15,15 +15,12 @@ use bumpalo::Bump;
use roc_can::abilities::{AbilitiesStore, MemberSpecializationInfo};
use roc_can::constraint::Constraint::{self, *};
use roc_can::constraint::{
Cycle, FxCallConstraint, FxSuffixConstraint, FxSuffixKind, LetConstraint, OpportunisticResolve,
TryTargetConstraint,
Cycle, FxCallConstraint, FxSuffixConstraint, FxSuffixKind, Generalizable, LetConstraint,
OpportunisticResolve, TryTargetConstraint,
};
use roc_can::expected::{Expected, PExpected};
use roc_can::module::ModuleParams;
use roc_collections::{VecMap, VecSet};
use roc_debug_flags::dbg_do;
#[cfg(debug_assertions)]
use roc_debug_flags::ROC_VERIFY_RIGID_LET_GENERALIZED;
use roc_error_macros::internal_error;
use roc_module::ident::IdentSuffix;
use roc_module::symbol::{ModuleId, Symbol};
@ -32,8 +29,8 @@ use roc_region::all::{Loc, Region};
use roc_solve_problem::TypeError;
use roc_solve_schema::UnificationMode;
use roc_types::subs::{
self, Content, FlatType, GetSubsSlice, Mark, OptVariable, Rank, Subs, TagExt, UlsOfVar,
Variable,
self, Content, ErrorTypeContext, FlatType, GetSubsSlice, Mark, OptVariable, Rank, Subs, TagExt,
UlsOfVar, Variable,
};
use roc_types::types::{Category, Polarity, Reason, RecordField, Type, TypeExtension, Types, Uls};
use roc_unify::unify::{
@ -356,29 +353,13 @@ fn solve(
generalize(env, young_mark, visit_mark, rank.next());
debug_assert!(env.pools.get(rank.next()).is_empty(), "variables left over in let-binding scope, but they should all be in a lower scope or generalized now");
// check that things went well
dbg_do!(ROC_VERIFY_RIGID_LET_GENERALIZED, {
let rigid_vars = &env.constraints[let_con.rigid_vars];
// NOTE the `subs.redundant` check does not come from elm.
// It's unclear whether this is a bug with our implementation
// (something is redundant that shouldn't be)
// or that it just never came up in elm.
let mut it = rigid_vars
.iter()
.filter(|loc_var| {
let var = loc_var.value;
!env.subs.redundant(var) && env.subs.get_rank(var) != Rank::GENERALIZED
})
.peekable();
if it.peek().is_some() {
let failing: Vec<_> = it.collect();
println!("Rigids {:?}", &rigid_vars);
println!("Failing {failing:?}");
debug_assert!(false);
}
});
let named_variables = &env.constraints[let_con.rigid_vars];
check_named_variables_are_generalized(
env,
problems,
named_variables,
let_con.generalizable,
);
let mut new_scope = scope.clone();
for (symbol, loc_var) in local_def_vars.iter() {
@ -1636,6 +1617,30 @@ fn solve(
state
}
fn check_named_variables_are_generalized(
env: &mut InferenceEnv<'_>,
problems: &mut Vec<TypeError>,
named_variables: &[Loc<Variable>],
generalizable: Generalizable,
) {
for loc_var in named_variables {
let is_generalized = env.subs.get_rank(loc_var.value) == Rank::GENERALIZED;
if !is_generalized {
// TODO: should be OF_PATTERN if on the LHS of a function, otherwise OF_VALUE.
let polarity = Polarity::OF_VALUE;
let ctx = ErrorTypeContext::NON_GENERALIZED_AS_INFERRED;
let error_type = env
.subs
.var_to_error_type_contextual(loc_var.value, ctx, polarity);
problems.push(TypeError::TypeIsNotGeneralized(
loc_var.region,
error_type,
generalizable,
));
}
}
}
fn solve_suffix_fx(
env: &mut InferenceEnv<'_>,
problems: &mut Vec<TypeError>,

View file

@ -2510,13 +2510,15 @@ mod solve_expr {
infer_eq_without_problem(
indoc!(
r"
empty : [Cons a (ConsList a), Nil] as ConsList a
empty = Nil
ConsList a : [Cons a (ConsList a), Nil]
empty
"
empty : ConsList _
empty = Nil
empty
"
),
"ConsList a",
"ConsList *",
);
}
@ -3742,7 +3744,7 @@ mod solve_expr {
indoc!(
r"
\rec ->
{ x, y } : { x : I64, y ? Bool }*
{ x, y } : { x : I64, y ? Bool }_
{ x, y ? Bool.false } = rec
{ x, y }
@ -3909,26 +3911,6 @@ mod solve_expr {
);
}
#[test]
fn double_named_rigids() {
infer_eq_without_problem(
indoc!(
r#"
app "test" provides [main] to "./platform"
main : List x
main =
empty : List x
empty = []
empty
"#
),
"List x",
);
}
#[test]
fn double_tag_application() {
infer_eq_without_problem(

View file

@ -1,7 +1,7 @@
//! Provides types to describe problems that can occur during solving.
use std::{path::PathBuf, str::Utf8Error};
use roc_can::constraint::{ExpectEffectfulReason, FxSuffixKind};
use roc_can::constraint::{ExpectEffectfulReason, FxSuffixKind, Generalizable};
use roc_can::expr::TryKind;
use roc_can::{
constraint::FxCallKind,
@ -50,6 +50,7 @@ pub enum TypeError {
UnsuffixedEffectfulFunction(Region, FxSuffixKind),
SuffixedPureFunction(Region, FxSuffixKind),
InvalidTryTarget(Region, ErrorType, TryKind),
TypeIsNotGeneralized(Region, ErrorType, Generalizable),
}
impl TypeError {
@ -80,6 +81,7 @@ impl TypeError {
TypeError::UnsuffixedEffectfulFunction(_, _) => Warning,
TypeError::SuffixedPureFunction(_, _) => Warning,
TypeError::InvalidTryTarget(_, _, _) => RuntimeError,
TypeError::TypeIsNotGeneralized(..) => RuntimeError,
}
}
@ -101,7 +103,8 @@ impl TypeError {
| TypeError::ExpectedEffectful(region, _)
| TypeError::UnsuffixedEffectfulFunction(region, _)
| TypeError::SuffixedPureFunction(region, _)
| TypeError::InvalidTryTarget(region, _, _) => Some(*region),
| TypeError::InvalidTryTarget(region, _, _)
| TypeError::TypeIsNotGeneralized(region, _, _) => Some(*region),
TypeError::UnfulfilledAbility(ab, ..) => ab.region(),
TypeError::Exhaustive(e) => Some(e.region()),
TypeError::CircularDef(c) => c.first().map(|ce| ce.symbol_region),

View file

@ -662,7 +662,7 @@ fn linked_list_len_1() {
LinkedList a : [Nil, Cons a (LinkedList a)]
one : LinkedList (Int *)
one : LinkedList (Int _)
one = Cons 1 Nil
length : LinkedList a -> Int *
@ -690,7 +690,7 @@ fn linked_list_len_twice_1() {
LinkedList a : [Nil, Cons a (LinkedList a)]
one : LinkedList (Int *)
one : LinkedList (Int _)
one = Cons 1 Nil
length : LinkedList a -> Int *
@ -718,7 +718,7 @@ fn linked_list_len_3() {
LinkedList a : [Nil, Cons a (LinkedList a)]
three : LinkedList (Int *)
three : LinkedList (Int _)
three = Cons 3 (Cons 2 (Cons 1 Nil))
length : LinkedList a -> Int *
@ -747,7 +747,7 @@ fn linked_list_sum_num_a() {
LinkedList a : [Nil, Cons a (LinkedList a)]
three : LinkedList (Int *)
three : LinkedList (Int _)
three = Cons 3 (Cons 2 (Cons 1 Nil))
@ -776,7 +776,7 @@ fn linked_list_sum_int() {
LinkedList a : [Nil, Cons a (LinkedList a)]
zero : LinkedList (Int *)
zero : LinkedList (Int _)
zero = Nil
sum : LinkedList (Int a) -> Int a
@ -804,7 +804,7 @@ fn linked_list_map() {
LinkedList a : [Nil, Cons a (LinkedList a)]
three : LinkedList (Int *)
three : LinkedList (Int _)
three = Cons 3 (Cons 2 (Cons 1 Nil))
sum : LinkedList (Num a) -> Num a
@ -836,7 +836,7 @@ fn when_nested_maybe() {
r"
Maybe a : [Nothing, Just a]
x : Maybe (Maybe (Int a))
x : Maybe (Maybe (Int _))
x = Just (Just 41)
when x is
@ -853,7 +853,7 @@ fn when_nested_maybe() {
r"
Maybe a : [Nothing, Just a]
x : Maybe (Maybe (Int *))
x : Maybe (Maybe (Int _))
x = Just Nothing
when x is
@ -871,7 +871,7 @@ fn when_nested_maybe() {
r"
Maybe a : [Nothing, Just a]
x : Maybe (Maybe (Int *))
x : Maybe (Maybe (Int _))
x = Nothing
when x is
@ -1402,7 +1402,7 @@ fn recursive_function_with_rigid() {
else
1 + foo { count: state.count - 1, x: state.x }
main : Int *
main : Int _
main =
foo { count: 3, x: {} }
"#
@ -1517,7 +1517,7 @@ fn rbtree_balance_3() {
balance = \key, left ->
Node key left Empty
main : RedBlackTree (Int *)
main : RedBlackTree (Int _)
main =
balance 0 Empty
"#
@ -1696,7 +1696,7 @@ fn nested_pattern_match_two_ways() {
_ -> 3
_ -> 3
main : Int *
main : Int _
main =
when balance Nil is
_ -> 3
@ -1719,7 +1719,7 @@ fn nested_pattern_match_two_ways() {
Cons 1 (Cons 1 _) -> 3
_ -> 3
main : Int *
main : Int _
main =
when balance Nil is
_ -> 3
@ -1751,7 +1751,7 @@ fn linked_list_guarded_double_pattern_match() {
_ -> 3
_ -> 3
main : Int *
main : Int _
main =
when balance Nil is
_ -> 3
@ -1778,7 +1778,7 @@ fn linked_list_double_pattern_match() {
Cons _ (Cons x _) -> x
_ -> 0
main : Int *
main : Int _
main =
foo (Cons 1 (Cons 32 Nil))
"#
@ -1886,7 +1886,7 @@ fn wildcard_rigid() {
@Effect inner
main : MyTask {} (Frac *)
main : MyTask {} (Frac _)
main = always {}
"#
),

View file

@ -135,7 +135,7 @@ fn err_type_var_annotation() {
assert_evals_to!(
indoc!(
r"
ok : Result I64 *
ok : Result I64 _
ok = Ok 3
Result.map_ok ok (\x -> x + 1)

View file

@ -1075,7 +1075,7 @@ fn applied_tag_function_result() {
assert_evals_to!(
indoc!(
r#"
x : List (Result Str *)
x : List (Result Str _)
x = List.map ["a", "b"] Ok
List.keep_oks x (\y -> y)

View file

@ -22,3 +22,4 @@ bumpalo.workspace = true
static_assertions.workspace = true
soa.workspace = true
bitflags.workspace = true

View file

@ -4,6 +4,7 @@ use crate::types::{
Polarity, RecordField, RecordFieldsError, TupleElemsError, TypeExt, Uls,
};
use crate::unification_table::{self, UnificationTable};
use bitflags::bitflags;
use roc_collections::all::{FnvMap, ImMap, ImSet, MutSet, SendMap};
use roc_collections::{VecMap, VecSet};
use roc_error_macros::internal_error;
@ -50,10 +51,23 @@ impl fmt::Debug for Mark {
}
}
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
pub enum ErrorTypeContext {
None,
ExpandRanges,
bitflags! {
pub struct ErrorTypeContext : u8 {
/// List all number types that satisfy number range constraints.
const EXPAND_RANGES = 1 << 0;
/// Re-write non-generalized types like to inference variables.
const NON_GENERALIZED_AS_INFERRED = 1 << 1;
}
}
impl ErrorTypeContext {
fn expand_ranges(&self) -> bool {
self.contains(Self::EXPAND_RANGES)
}
fn non_generalized_as_inferred(&self) -> bool {
self.contains(Self::NON_GENERALIZED_AS_INFERRED)
}
}
struct ErrorTypeState {
@ -2055,7 +2069,7 @@ impl Subs {
}
pub fn var_to_error_type(&mut self, var: Variable, observed_pol: Polarity) -> ErrorType {
self.var_to_error_type_contextual(var, ErrorTypeContext::None, observed_pol)
self.var_to_error_type_contextual(var, ErrorTypeContext::empty(), observed_pol)
}
pub fn var_to_error_type_contextual(
@ -4020,6 +4034,13 @@ fn content_to_err_type(
match content {
Structure(flat_type) => flat_type_to_err_type(subs, state, flat_type, pol),
RigidVar(..) | RigidAbleVar(..)
if state.context.non_generalized_as_inferred()
&& subs.get_rank(var) != Rank::GENERALIZED =>
{
ErrorType::InferenceVar
}
FlexVar(opt_name) => {
let name = match opt_name {
Some(name_index) => subs.field_names[name_index.index()].clone(),
@ -4123,7 +4144,7 @@ fn content_to_err_type(
}
RangedNumber(range) => {
if state.context == ErrorTypeContext::ExpandRanges {
if state.context.expand_ranges() {
let mut types = Vec::new();
for var in range.variable_slice() {
types.push(var_to_err_type(subs, state, *var, pol));

View file

@ -3679,6 +3679,7 @@ pub enum ErrorType {
/// If the name was auto-generated, it will start with a `#`.
FlexVar(Lowercase),
RigidVar(Lowercase),
InferenceVar,
EffectfulFunc,
/// If the name was auto-generated, it will start with a `#`.
FlexAbleVar(Lowercase, AbilitySet),
@ -3733,6 +3734,7 @@ impl ErrorType {
FlexVar(v) | RigidVar(v) | FlexAbleVar(v, _) | RigidAbleVar(v, _) => {
taken.insert(v.clone());
}
InferenceVar => {}
Record(fields, ext) => {
fields
.iter()
@ -3912,13 +3914,14 @@ fn write_debug_error_type_help(error_type: ErrorType, buf: &mut String, parens:
Infinite => buf.push('∞'),
Error => buf.push('?'),
FlexVar(name) | RigidVar(name) => buf.push_str(name.as_str()),
FlexAbleVar(name, symbol) | RigidAbleVar(name, symbol) => {
InferenceVar => buf.push('_'),
FlexAbleVar(name, abilities) | RigidAbleVar(name, abilities) => {
let write_parens = parens == Parens::InTypeParam;
if write_parens {
buf.push('(');
}
buf.push_str(name.as_str());
write!(buf, "{} {:?}", roc_parse::keyword::IMPLEMENTS, symbol).unwrap();
write!(buf, "{} {:?}", roc_parse::keyword::IMPLEMENTS, abilities).unwrap();
if write_parens {
buf.push(')');
}

View file

@ -1,9 +0,0 @@
app "test" provides [foo] to "./platform"
F a : { foo : a }
foo = \arg ->
#^^^{-1} F b -[[foo(0)]]-> b
x : F b
x = arg
x.foo

View file

@ -356,9 +356,9 @@ fn unify_help<M: MetaCollector>(
}
} else {
let error_context = if mismatches.contains(&Mismatch::TypeNotInRange) {
ErrorTypeContext::ExpandRanges
ErrorTypeContext::EXPAND_RANGES
} else {
ErrorTypeContext::None
ErrorTypeContext::empty()
};
let type1 = env.var_to_error_type_contextual(var1, error_context, observed_pol);