diff options
Diffstat (limited to 'src/parser.zig')
| -rw-r--r-- | src/parser.zig | 72 |
1 files changed, 37 insertions, 35 deletions
diff --git a/src/parser.zig b/src/parser.zig index e9a2908..cf7f7d3 100644 --- a/src/parser.zig +++ b/src/parser.zig @@ -108,7 +108,7 @@ pub const Parser = struct { const statement = self.accept_parse(parse_function_call_statement) orelse try self.parse_assignment_statement(); - _ = try self.accept_token(tokenizer.TokenType.SEMICOLON); + _ = try self.require_token(tokenizer.TokenType.SEMICOLON); return self.create_node(.{ .STATEMENT = .{ @@ -122,13 +122,13 @@ pub const Parser = struct { errdefer if (!self.try_context) std.debug.print("Error parsing assignment statement\n", .{}); var is_declaration: bool = false; - if (self.match_token(.LET) != null) { + if (self.accept_token(.LET) != null) { is_declaration = true; } - const identifier = try self.accept_token(tokenizer.TokenType.IDENTIFIER); + const identifier = try self.require_token(tokenizer.TokenType.IDENTIFIER); - _ = try self.accept_token(tokenizer.TokenType.EQUALS); + _ = try self.require_token(tokenizer.TokenType.EQUALS); const expression = try self.parse_expression(); @@ -145,13 +145,13 @@ pub const Parser = struct { fn parse_function_call_statement(self: *Parser) ParserError!*Node { errdefer if (!self.try_context) std.debug.print("Error parsing function call statement\n", .{}); - const identifier = try self.accept_token(tokenizer.TokenType.IDENTIFIER); + const identifier = try self.require_token(tokenizer.TokenType.IDENTIFIER); - _ = try self.accept_token(tokenizer.TokenType.LPAREN); + _ = try self.require_token(tokenizer.TokenType.LPAREN); const arguments = try self.parse_function_arguments(); - _ = try self.accept_token(tokenizer.TokenType.RPAREN); + _ = try self.require_token(tokenizer.TokenType.RPAREN); return self.create_node(.{ .FUNCTION_CALL_STATEMENT = .{ .name = try self.allocator.dupe(u8, identifier.IDENTIFIER), @@ -162,18 +162,19 @@ pub const Parser = struct { // FunctionArguments ::= Expression ("," Expression)* fn parse_function_arguments(self: *Parser) ParserError![]*Node { errdefer if (!self.try_context) std.debug.print("Error parsing function arguments\n", .{}); - var nodeList = std.ArrayList(*Node).init(self.allocator); + var node_list = std.ArrayList(*Node).init(self.allocator); var first = true; - while (self.accept_parse(parse_expression)) |a| { + while (true) { if (!first) { - _ = try self.accept_token(tokenizer.TokenType.COMMA); + _ = self.accept_token(tokenizer.TokenType.COMMA); } first = false; - try nodeList.append(a); + const expr = self.accept_parse(parse_expression) orelse return node_list.items; + try node_list.append(expr); } - return nodeList.items; + return node_list.items; } // Expression ::= AdditiveExpression | FunctionDefinition @@ -191,7 +192,7 @@ pub const Parser = struct { const lhs = try self.parse_primary_expression(); - if (self.match_token(tokenizer.TokenType.PLUS) != null) { + if (self.accept_token(tokenizer.TokenType.PLUS) != null) { const rhs = try self.parse_additive_expression(); return self.create_node(.{ .ADDITIVE_EXPRESSION = .{ .lhs = lhs, @@ -233,14 +234,14 @@ pub const Parser = struct { fn parse_function_definition(self: *Parser) ParserError!*Node { errdefer if (!self.try_context) std.debug.print("Error parsing function definition\n", .{}); - _ = try self.accept_token(tokenizer.TokenType.LPAREN); + _ = try self.require_token(tokenizer.TokenType.LPAREN); const parameters = try self.parse_function_parameters(); - _ = try self.accept_token(tokenizer.TokenType.RPAREN); + _ = try self.require_token(tokenizer.TokenType.RPAREN); - _ = try self.accept_token(tokenizer.TokenType.ARROW); - _ = try self.accept_token(tokenizer.TokenType.LBRACE); + _ = try self.require_token(tokenizer.TokenType.ARROW); + _ = try self.require_token(tokenizer.TokenType.LBRACE); var nodes = std.ArrayList(*Node).init(self.allocator); while (self.accept_parse(parse_statement)) |expression| { @@ -249,7 +250,7 @@ pub const Parser = struct { try nodes.append(try self.parse_return_statement()); - _ = try self.accept_token(tokenizer.TokenType.RBRACE); + _ = try self.require_token(tokenizer.TokenType.RBRACE); return self.create_node(.{ .FUNCTION_DEFINITION = .{ .statements = nodes.items, @@ -260,35 +261,36 @@ pub const Parser = struct { // FunctionParameters ::= IDENTIFIER ("," IDENTIFIER)* fn parse_function_parameters(self: *Parser) ParserError![]*Node { errdefer if (!self.try_context) std.debug.print("Error parsing function parameters\n", .{}); - var nodeList = std.ArrayList(*Node).init(self.allocator); + var node_list = std.ArrayList(*Node).init(self.allocator); var first = true; - while (self.match_token(tokenizer.TokenType.IDENTIFIER)) |a| { + while (true) { if (!first) { - _ = try self.accept_token(tokenizer.TokenType.COMMA); + _ = self.accept_token(tokenizer.TokenType.COMMA); } first = false; + const ident = self.accept_token(tokenizer.TokenType.IDENTIFIER) orelse return node_list.items; - try nodeList.append(try self.create_node(.{ + try node_list.append(try self.create_node(.{ .PRIMARY_EXPRESSION = .{ .IDENTIFIER = .{ - .name = try self.allocator.dupe(u8, a.IDENTIFIER), + .name = try self.allocator.dupe(u8, ident.IDENTIFIER), }, }, })); } - return nodeList.items; + return node_list.items; } // ReturnStatement :== RETURN Expression fn parse_return_statement(self: *Parser) ParserError!*Node { errdefer if (!self.try_context) std.debug.print("Error parsing return statement\n", .{}); - _ = try self.accept_token(tokenizer.TokenType.RETURN); + _ = try self.require_token(tokenizer.TokenType.RETURN); const expression = try self.parse_expression(); - _ = try self.accept_token(tokenizer.TokenType.SEMICOLON); //TODO: I dont like this + _ = try self.require_token(tokenizer.TokenType.SEMICOLON); //TODO: I dont like this return self.create_node(.{ .RETURN_STATEMENT = .{ @@ -308,7 +310,15 @@ pub const Parser = struct { return node; } - fn accept_token(self: *Parser, expected_token: tokenizer.TokenType) ParserError!tokenizer.Token { + fn accept_token(self: *Parser, token: tokenizer.TokenType) ?tokenizer.Token { + const curr_token = self.peek_token() orelse return null; + if (curr_token == token) { + return self.consume_token(); + } + return null; + } + + fn require_token(self: *Parser, expected_token: tokenizer.TokenType) ParserError!tokenizer.Token { errdefer if (!self.try_context) std.debug.print("Error accepting token: {any}\n", .{expected_token}); const token = self.peek_token() orelse return ParserError.ParsingError; @@ -320,14 +330,6 @@ pub const Parser = struct { return self.consume_token() orelse unreachable; } - fn match_token(self: *Parser, token: tokenizer.TokenType) ?tokenizer.Token { - const curr_token = self.peek_token() orelse return null; - if (curr_token == token) { - return self.consume_token(); - } - return null; - } - fn consume_token(self: *Parser) ?tokenizer.Token { if (self.offset >= self.tokens.len) return null; |