Fix if-statement block return type evaluation

This commit is contained in:
Sofia 2025-07-14 17:17:48 +03:00
parent bad4713779
commit b64cdc4c71
2 changed files with 29 additions and 11 deletions

View File

@ -19,7 +19,7 @@
//!
//! An example program of Reid, that calculates the 5th fibonacci number (and
//! uses Rust for highlighting) is:
//! ```rust
//! ```reid
//! fn main() -> u16 {
//! return fibonacci(5);
//! }
@ -30,6 +30,7 @@
//! }
//! return fibonacci(n-1) + fibonacci(n-2);
//! }
//! ```
//!
//! Currently missing relevant features (TODOs) are:
//! - ~~Arrays~~ (DONE)

View File

@ -91,13 +91,13 @@ impl FunctionDefinition {
state.scope.return_type_hint = Some(self.return_type.clone());
block.typecheck(state, &hints, Some(&return_type))
}
FunctionDefinitionKind::Extern => Ok(Vague(Unknown)),
FunctionDefinitionKind::Extern => Ok((ReturnKind::Soft, Vague(Unknown))),
};
match inferred {
Ok(t) => return_type
.collapse_into(&t)
.or(Err(ErrorKind::ReturnTypeMismatch(return_type, t))),
.collapse_into(&t.1)
.or(Err(ErrorKind::ReturnTypeMismatch(return_type, t.1))),
Err(e) => Ok(state.or_else(Err(e), return_type, self.block_meta())),
}
}
@ -109,7 +109,7 @@ impl Block {
state: &mut PassState<ErrorKind>,
hints: &TypeRefs,
hint_t: Option<&TypeKind>,
) -> Result<TypeKind, ErrorKind> {
) -> Result<(ReturnKind, TypeKind), ErrorKind> {
let mut state = state.inner();
let mut early_return = None;
@ -233,7 +233,7 @@ impl Block {
if let Some((ReturnKind::Hard, expr)) = early_return {
let hint = state.scope.return_type_hint.clone();
let res = expr.typecheck(&mut state, &hints, hint.as_ref());
return Ok(state.or_else(res, Vague(Unknown), expr.1));
return Ok((ReturnKind::Hard, state.or_else(res, Vague(Unknown), expr.1)));
}
if let Some((return_kind, expr)) = &mut self.return_expression {
@ -243,9 +243,9 @@ impl Block {
ReturnKind::Soft => hint_t.cloned(),
};
let res = expr.typecheck(&mut state, &hints, ret_hint_t.as_ref());
Ok(state.or_else(res, Vague(Unknown), expr.1))
Ok((*return_kind, state.or_else(res, Vague(Unknown), expr.1)))
} else {
Ok(Void)
Ok((ReturnKind::Soft, Void))
}
}
}
@ -359,14 +359,27 @@ impl Expression {
// Typecheck then/else return types and make sure they are the
// same, if else exists.
let then_res = lhs.typecheck(state, &hints, hint_t);
let then_ret_t = state.or_else(then_res, Vague(Unknown), lhs.meta);
let (then_ret_kind, then_ret_t) =
state.or_else(then_res, (ReturnKind::Soft, Vague(Unknown)), lhs.meta);
let else_ret_t = if let Some(else_block) = rhs {
let res = else_block.typecheck(state, &hints, hint_t);
state.or_else(res, Vague(Unknown), else_block.meta)
let (else_ret_kind, else_ret_t) =
state.or_else(res, (ReturnKind::Soft, Vague(Unknown)), else_block.meta);
if else_ret_kind == ReturnKind::Hard {
Void
} else {
else_ret_t
}
} else {
// Else return type is Void if it does not exist
Void
};
let then_ret_t = if then_ret_kind == ReturnKind::Hard {
Void
} else {
then_ret_t
};
// Make sure then and else -blocks have the same return type
let collapsed = then_ret_t
@ -384,7 +397,11 @@ impl Expression {
Ok(collapsed)
}
ExprKind::Block(block) => block.typecheck(state, &hints, hint_t),
ExprKind::Block(block) => match block.typecheck(state, &hints, hint_t) {
Ok((ReturnKind::Hard, _)) => Ok(Void),
Ok((_, ty)) => Ok(ty),
Err(e) => Err(e),
},
ExprKind::Index(expression, elem_ty, idx) => {
// Try to unwrap hint type from array if possible
let hint_t = hint_t.map(|t| match t {