some parsing

bong_grammar.txt

@@ -16,23 +16,26 @@ element_field ->
     | element_property
     | value
 
+element_property -> Name _ ("=" | ":") _ value
+
 single_line_fields ->
     (first_single_line_field
-        (__singleline__ single_line_field):*):? __singleline__
+        (__singleline__ single_line_field):*):? _singleline_
 
 first_single_line_field ->
     | Id
     | Class
-    | __singleline__ element_property
+    | __singleline__ single_line_element_property
     | __singleline__ single_line_value
 
 single_line_field ->
     | Id
     | Class
-    | element_property
+    | single_line_element_property
     | single_line_value
 
-element_property -> Name _ ("=" | ":") _ value
+single_line_element_property ->
+    Name _singleline_ ("=" | ":") _singleline_ value
 
 single_line_value ->
     | array
@@ -77,7 +80,7 @@ mandatory_linebreak ->
     line_breaker
     whitespace_and_line_break:*
 
-single_line_whitespace -> SingleLineComment | SingleLineWhitespace
+single_line_whitespace -> SingleLineWhitespace | MultiLineComment
 
 line_breaker -> MultiLineComment | MultiLineWhitespace | ";"
 

src/bong.cpp

@@ -342,7 +342,7 @@ auto Lexer::step() noexcept -> void
 auto Parser::parse_top_level() noexcept -> Result<std::unique_ptr<Node>, Error>
 {
     if (!lexer.peek())
-        return { lexer.peek().unwrap_error() };
+        return Error { lexer.peek().unwrap_error() };
     else if (lexer.peek()->type == Tokens::Name)
         return parse_element();
     else
@@ -358,8 +358,8 @@ auto Parser::parse_element() noexcept -> Result<std::unique_ptr<Node>, Error>
     auto properties = Element::Properties {};
     auto values = Element::Values {};
 
-    if (!lexer.next())
-        return { lexer.peek().unwrap_error() };
+    if (auto result = lexer.next(); !result)
+        return Error { result.unwrap_error() };
     return Result<std::unique_ptr<Node>, Error>::create_ok(
         std::make_unique<Element>(
             Element { std::string { name.value() }, {}, {}, {}, {} }));
@@ -368,9 +368,54 @@ auto Parser::parse_element() noexcept -> Result<std::unique_ptr<Node>, Error>
 auto Parser::parse_single_line_fields(
     Element::Initializer& initializer) noexcept -> Result<void, Error>
 {
-    if (auto result = parse_first_single_line_field(initializer); !result)
-        return result;
-    return {};
+    if (lexer.peek()->type == Tokens::Id) {
+        initializer.ids.push_back(std::string { lexer.peek()->value() });
+        if (auto result = lexer.next(); !result)
+            return Error { result.unwrap_error() };
+        // do the rest;
+    } else if (lexer.peek()->type == Tokens::Class) {
+        initializer.classes.push_back(std::string { lexer.peek()->value() });
+        if (auto result = lexer.next(); !result)
+            return Error { result.unwrap_error() };
+        // do the rest
+    } else {
+        if (auto result = parse_mandatory_same_line_whitespace(); !result)
+            return result;
+        if (lexer.peek()->type == Tokens::Name) {
+            auto key = lexer.peek();
+            if (auto result = lexer.next(); !result)
+                return Error { result.unwrap_error() };
+            if (auto result = parse_optional_whitespace(); !result)
+                return result;
+            if (lexer.peek()->type != Tokens::Equal
+                and lexer.peek()->type != Tokens::Colon)
+                return Error {
+                    fmt::format("expected '=' or ':', got {}",
+                        lexer.peek()->to_string()),
+                    lexer.peek()->location,
+                };
+            if (auto result = lexer.next(); !result)
+                return Error { result.unwrap_error() };
+            if (auto result = parse_optional_same_line_whitespace(); !result)
+                return result;
+            auto value = parse_single_line_value();
+            if (!value)
+                return value;
+            // do the rest
+        } else {
+            auto value = parse_single_line_value();
+            if (!value)
+                return value;
+            // do the rest
+        }
+    }
 }
 
+// auto Parser::parse_single_line_field(Element::Initializer& initializer)
+// noexcept
+//     -> Result<void, Error>
+// {
+
+// }
+
 }

src/bong.hpp

@@ -204,10 +204,14 @@ struct Bool final : public Node {
 class Parser {
 public:
     struct Error {
-        Error(Lexer::Error&& error)
+        Error(Lexer::Error error)
             : message { std::move(error.message) }
             , location { error.location }
         { }
+        Error(std::string message, Location location)
+            : message { std::move(message) }
+            , location { location }
+        { }
 
         std::string message;
         Location location;
@@ -227,10 +231,6 @@ public:
         -> Result<void, Error>;
     auto parse_single_line_fields(Element::Initializer& initializer) noexcept
         -> Result<void, Error>;
-    auto parse_first_single_line_field(
-        Element::Initializer& initializer) noexcept -> Result<void, Error>;
-    auto parse_single_line_field(Element::Initializer& initializer) noexcept
-        -> Result<void, Error>;
     auto parse_element_property() noexcept -> Result<void, Error>;
     auto parse_single_line_value() noexcept -> Result<void, Error>;
     auto parse_value() noexcept -> Result<std::unique_ptr<Node>, Error>;

src/main.cpp

@@ -78,14 +78,7 @@ auto read_file_into_string(const std::string& filename)
         std::istreambuf_iterator<char>(file), std::istreambuf_iterator<char>());
     return contents;
 }
-struct Data {
-    int a, b;
-};
 
-auto func() -> std::unique_ptr<Data>
-{
-    return std::make_unique<Data>(Data { 5, 3 });
-}
 auto main() -> int
 {