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Resolver - Errors on undefined symbols

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This commit is contained in:
Emmanuel BENOîT 2023-01-07 11:10:24 +01:00
parent 06917ca2d6
commit 4bce85e14b
1 changed files with 20 additions and 15 deletions
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35
src/resolver.rs
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@ -114,19 +114,14 @@ impl ResolverState {
i -= 1;
if let Some(info) = self.scopes[i].get_mut(&name.lexeme as &str) {
if info.state == SymState::Declared {
return Err(SloxError::with_token(
ErrorKind::Parse,
name,
"symbol accessed before definition".to_owned(),
));
return self.error(name, "symbol accessed before definition");
}
info.state = SymState::Used;
self.mark_resolved(expr_id, i);
return Ok(());
}
}
// XXX not found !
Ok(())
self.symbol_not_found(name)
}
/// Resolve a symbol when it is being assigned to. If the symbol is local,
@ -138,11 +133,7 @@ impl ResolverState {
i -= 1;
if let Some(info) = self.scopes[i].get_mut(&name.lexeme as &str) {
if info.kind != SymKind::Variable {
return Err(SloxError::with_token(
ErrorKind::Parse,
name,
"cannot assign to this symbol".to_owned(),
));
return self.error(name, "cannot assign to this symbol");
}
if info.state == SymState::Declared {
info.state = SymState::Defined;
@ -151,17 +142,31 @@ impl ResolverState {
return Ok(());
}
}
// XXX not found !
Ok(())
self.symbol_not_found(name)
}
/// Add an entry to the resolution map for an AST node.
fn mark_resolved(&mut self, expr_id: &usize, depth: usize) {
// Only mark symbols as locals if we're not at the top-level scope.
if depth != 0 {
self.resolved.insert(*expr_id, self.scopes.len() - 1 - depth);
self.resolved
.insert(*expr_id, self.scopes.len() - 1 - depth);
}
}
/// Return an error corresponding to an undeclared symbol.
fn symbol_not_found(&mut self, name: &Token) -> ResolverResult {
self.error(name, "undeclared symbol")
}
/// Return an error.
fn error(&mut self, name: &Token, message: &str) -> ResolverResult {
Err(SloxError::with_token(
ErrorKind::Parse,
name,
message.to_owned(),
))
}
}
/// Process a function declaration.