public static LinkedListNode<Lexeme> TryParse(LinkedListNode<Lexeme> lexemes, out Node resultNode)
{
resultNode = null;
var nextLexeme = StructDecl.TryParse(lexemes, out StructDecl structDecl);
if (structDecl != null)
{
resultNode = structDecl;
return nextLexeme;
}
nextLexeme = FnDecl.TryParse(lexemes, out FnDecl fn);
if (fn != null)
{
resultNode = fn;
return nextLexeme;
}
nextLexeme = Stmt.TryParseStruct(lexemes, out Stmt stmt);
if (stmt != null)
{
resultNode = stmt;
return nextLexeme;
}
return lexemes;
}
public static LinkedListNode <Lexeme> TryParse(LinkedListNode <Lexeme> lexemes, out StructDecl resultNode)
{
resultNode = null;
if (lexemes.Value.Type != LT.KW_STRUCT)
{
return(lexemes);
}
var nextLexeme = lexemes.Next;
if (nextLexeme.Value.Type != LT.IDENT)
{
throw new Exception($"Missing struct name at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
var nameLexeme = nextLexeme.Value;
nextLexeme = nextLexeme.Next;
if (nextLexeme.Value.Type != LT.OP_BRACE_O)
{
throw new Exception($"Missing opening bracket for struct at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
List <Stmt> stmts = new List <Stmt>();
nextLexeme = nextLexeme.Next;
while (true)
{
nextLexeme = Stmt.TryParseStruct(nextLexeme, out Stmt stmt);
if (stmt != null)
{
stmts.Add(stmt);
}
else
{
break;
}
}
if (stmts.Count == 0)
{
throw new Exception($"Missing struct body at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
if (nextLexeme.Value.Type != LT.OP_BRACE_C)
{
throw new Exception($"Missing closing bracket for struct at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
resultNode = new StructDecl {
Body = new BlockBody(stmts), Token = nameLexeme
};
return(nextLexeme.Next);
}