helper function for parsing text within () or {}

src/ast2/mod.rs

@@ -1036,6 +1036,8 @@ enum ParseError {
     ExpectedEndOfBlock,
     #[error("Dummy Message.")]
     UnmatchedBrace(u32),
+    #[error("Dummy Message.")]
+    UnmatchedDelimiter(u32),
     #[error("Error in child node {0:?}.")]
     ErrorNode(Index),
 }
@@ -2324,40 +2326,14 @@ pub mod ast_gen {
 
             let ident = self.parse_ident(tokens)?;
 
-            let Some(open_parens) = tokens.eat_token(Token::OpenParens) else {
+            let parameters = self.parse_parenthesised(tokens, |this, tokens| {
-                return Err(ErrorInfo {
+                if tokens.is_next_token(Token::CloseParens) {
-                    error: ParseError::ExpectedArgumentList,
+                    Ok(this.ast.push_parameter_list([], loc))
-                    loc,
-                });
-            };
-
-            let parameters = if tokens.is_next_token(Token::CloseParens) {
-                self.ast.push_parameter_list([], loc)
                 } else {
-                match self.parse_parameter_list(tokens) {
+                    this.parse_parameter_list(tokens)
-                    Ok(i) => {
-                        _ = tokens.eat_token(Token::Comma);
-
-                        let Some(_) = tokens.eat_token(Token::CloseParens) else {
-                            return Err(ErrorInfo {
-                                error: ParseError::UnmatchedParens(open_parens.token_pos().start),
-                                loc: tokens.current_source_location(),
-                            });
-                        };
-
-                        i
                 }
-                    Err(err) => {
-                        tokens.advance_past_end_of_parens().ok_or(ErrorInfo {
-                            error: ParseError::UnmatchedParens(open_parens.token_pos().start),
-                            loc: tokens.current_source_location(),
             })?;
 
-                        self.push_error(err.error, err.loc)
-                    }
-                }
-            };
-
             let return_type = if let Some(_) = tokens.eat_token(Token::MinusGreater) {
                 self.parse_type(tokens)?
             } else {
@@ -3197,6 +3173,134 @@ pub mod ast_gen {
             }
         }
 
+        fn parse_with_trailing_semi<F>(
+            &mut self,
+            tokens: &mut TokenIterator,
+            parse: F,
+        ) -> ParseResult<Index>
+        where
+            F: FnOnce(&mut Self, &mut TokenIterator) -> ParseResult<Index>,
+        {
+            match parse(self, tokens) {
+                Ok(i) => {
+                    _ = tokens.eat_token(Token::Semi).ok_or(ErrorInfo {
+                        error: ParseError::ExpectedToken(Token::Semi),
+                        loc: tokens.current_source_location(),
+                    })?;
+
+                    Ok(i)
+                }
+                Err(err) => {
+                    tokens.advance_past_semi().ok_or(ErrorInfo {
+                        error: ParseError::ExpectedToken(Token::Semi),
+                        loc: tokens.current_source_location(),
+                    })?;
+                    Ok(self.push_error(err.error, err.loc))
+                }
+            }
+        }
+
+        fn parse_inner<F, E>(
+            &mut self,
+            tokens: &mut TokenIterator,
+            open: Token,
+            close: Token,
+            parse: F,
+            on_err: E,
+        ) -> ParseResult<Index>
+        where
+            F: FnOnce(&mut Self, &mut TokenIterator) -> ParseResult<Index>,
+            E: FnOnce(&mut Self, &mut TokenIterator, ErrorInfo, TokenItem) -> ParseResult<Index>,
+        {
+            let Some(start) = tokens.eat_token(open) else {
+                return Err(ErrorInfo {
+                    error: ParseError::ExpectedToken(open),
+                    loc: tokens.current_source_location(),
+                });
+            };
+
+            match parse(self, tokens) {
+                Ok(i) => {
+                    _ = tokens.eat_token(close).ok_or(ErrorInfo {
+                        error: match open {
+                            Token::OpenBrace => ParseError::UnmatchedBrace(start.token_pos().start),
+                            Token::OpenParens => {
+                                ParseError::UnmatchedParens(start.token_pos().start)
+                            }
+                            Token::OpenSquareBracket => {
+                                ParseError::UnmatchedSquareBracket(start.token_pos().start)
+                            }
+                            _ => ParseError::UnmatchedDelimiter(start.token_pos().start),
+                        },
+                        loc: tokens.current_source_location(),
+                    })?;
+
+                    Ok(i)
+                }
+                Err(e) => on_err(self, tokens, e, start),
+            }
+        }
+
+        fn parse_inner2<F>(
+            &mut self,
+            tokens: &mut TokenIterator,
+            open: Token,
+            close: Token,
+            parse: F,
+        ) -> ParseResult<Index>
+        where
+            F: FnOnce(&mut Self, &mut TokenIterator) -> ParseResult<Index>,
+        {
+            self.parse_inner(tokens, open, close, parse, |this, tokens, err, start| {
+                match close {
+                    Token::CloseBrace => {
+                        tokens.advance_past_end_of_braced().ok_or(ErrorInfo {
+                            error: ParseError::UnmatchedBrace(start.token_pos().start),
+                            loc: tokens.current_source_location(),
+                        })?;
+                    }
+                    Token::CloseParens => {
+                        tokens.advance_past_end_of_parens().ok_or(ErrorInfo {
+                            error: ParseError::UnmatchedParens(start.token_pos().start),
+                            loc: tokens.current_source_location(),
+                        })?;
+                    }
+                    Token::CloseSquareBracket => {
+                        tokens.advance_past_end_of_bracketed().ok_or(ErrorInfo {
+                            error: ParseError::UnmatchedSquareBracket(start.token_pos().start),
+                            loc: tokens.current_source_location(),
+                        })?;
+                    }
+                    Token::Semi => {
+                        tokens.advance_past_semi().ok_or(ErrorInfo {
+                            error: ParseError::ExpectedToken(Token::Semi),
+                            loc: tokens.current_source_location(),
+                        })?;
+                    }
+                    _ => unimplemented!(),
+                }
+                Ok(this.push_error(err.error, err.loc))
+            })
+        }
+
+        fn parse_braced<F>(&mut self, tokens: &mut TokenIterator, parse: F) -> ParseResult<Index>
+        where
+            F: FnOnce(&mut Self, &mut TokenIterator) -> ParseResult<Index>,
+        {
+            self.parse_inner2(tokens, Token::OpenBrace, Token::CloseBrace, parse)
+        }
+
+        fn parse_parenthesised<F>(
+            &mut self,
+            tokens: &mut TokenIterator,
+            parse: F,
+        ) -> ParseResult<Index>
+        where
+            F: FnOnce(&mut Self, &mut TokenIterator) -> ParseResult<Index>,
+        {
+            self.parse_inner2(tokens, Token::OpenParens, Token::CloseParens, parse)
+        }
+
         fn parse_struct_fields(
             &mut self,
             tokens: &mut TokenIterator,