language-servers/roc
1
0
Fork 0
mirror of https://github.com/roc-lang/roc.git synced 2025-09-28 06:14:46 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

Recursive vars in occurs check can happen anywhere in the chain

Browse source
This commit is contained in:
Ayaz Hafiz 2022-08-09 16:07:59 -07:00
parent f20d1ac59a
commit 3f1e11f920
No known key found for this signature in database
GPG key ID: 0E2A37416A25EF58
1 changed files with 24 additions and 18 deletions
Download patch file Download diff file Expand all files Collapse all files

42
crates/compiler/solve/src/solve.rs
View file

@ -2876,28 +2876,34 @@ fn check_for_infinite_type(
) { ) {
let var = loc_var.value; let var = loc_var.value;
while let Err((recursive, _chain)) = subs.occurs(var) { 'next_occurs_check: while let Err((_, chain)) = subs.occurs(var) {
// try to make a union recursive, see if that helps // walk the chain till we find a tag union or lambda set, starting from the variable that
match subs.get_content_without_compacting(recursive) { // occurred recursively, which is always at the end of the chain.
&Content::Structure(FlatType::TagUnion(tags, ext_var)) => { for &var in chain.iter().rev() {
subs.mark_tag_union_recursive(recursive, tags, ext_var); match subs.get_content_without_compacting(var) {
} &Content::Structure(FlatType::TagUnion(tags, ext_var)) => {
&Content::LambdaSet(subs::LambdaSet { subs.mark_tag_union_recursive(var, tags, ext_var);
solved, continue 'next_occurs_check;
recursion_var: _, }
unspecialized, &Content::LambdaSet(subs::LambdaSet {
ambient_function: ambient_function_var,
}) => {
subs.mark_lambda_set_recursive(
recursive,
solved, solved,
recursion_var: _,
unspecialized, unspecialized,
ambient_function_var, ambient_function: ambient_function_var,
); }) => {
subs.mark_lambda_set_recursive(
var,
solved,
unspecialized,
ambient_function_var,
);
continue 'next_occurs_check;
}
_ => { /* fall through */ }
} }
_other => circular_error(subs, problems, symbol, &loc_var),
} }
circular_error(subs, problems, symbol, &loc_var);
} }
} }