public static LinkedListNode <Lexeme> TryParse(LinkedListNode <Lexeme> lexemes, out FnCall resultNode)
{
List <Expr> exprs = new List <Expr>();
resultNode = null;
if (lexemes.Value.Type != LT.IDENT)
{
return(lexemes);
}
Lexeme token = lexemes.Value;
var nextLexeme = lexemes.Next;
if (nextLexeme.Value.Type != LT.OP_PAREN_O)
{
return(lexemes);
}
nextLexeme = nextLexeme.Next;
nextLexeme = Expr.TryParse(nextLexeme, out Expr expr);
if (expr == null)
{
resultNode = new FnCall {
Args = exprs, Token = token
};
return(nextLexeme);
}
exprs.Add(expr);
while (nextLexeme.Value.Type == LT.OP_COMMA)
{
nextLexeme = nextLexeme.Next;
nextLexeme = Expr.TryParse(nextLexeme, out expr);
if (expr == null)
{
throw new Exception($"Trailing comma at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
exprs.Add(expr);
}
resultNode = new FnCall {
Args = exprs, Token = token
};
if (nextLexeme.Value.Type == LT.OP_PAREN_C)
{
nextLexeme = nextLexeme.Next;
}
else
{
throw new Exception($"Missing closing parenthesis at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
return(nextLexeme);
}
public static LinkedListNode <Lexeme> TryParseNoLit(LinkedListNode <Lexeme> lexemes, out Expr resultNode)
{
Expr node = null;
resultNode = null;
LinkedListNode <Lexeme> nextLexeme = lexemes;
if (lexemes.Value.Type == LT.OP_PAREN_O)
{
nextLexeme = BinaryExpr.TryParseExpr(lexemes.Next, out Expr expr);
if (expr != null)
{
node = expr;
if (nextLexeme.Value.Type != LT.OP_PAREN_C)
{
throw new Exception($"Missing closing parenthesis at {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
nextLexeme = nextLexeme.Next;
}
}
if (node == null)
{
nextLexeme = FnCall.TryParse(lexemes, out FnCall fnc);
node = fnc;
}
if (node == null)
{
nextLexeme = Var.TryParse(lexemes, out Var v);
node = v;
}
if (node == null)
{
return(lexemes);
}
while (nextLexeme.Value.Type == LT.OP_PNT)
{
nextLexeme = Var.TryParse(nextLexeme.Next, out Var v);
if (v == null)
{
throw new Exception($"No trailing points allowed! At {nextLexeme.Value.File}:{nextLexeme.Value.Line}");
}
node = new PointExpr {
Left = node, Right = v
};
}
resultNode = node;
return(nextLexeme);
}
public static LinkedListNode <Lexeme> TryParse(LinkedListNode <Lexeme> lexemes, out Stmt resultNode)
{
resultNode = null;
if (lexemes.Value.Type == LT.OP_SC)
{
resultNode = new BlankStmt();
return(lexemes.Next);
}
var nextLexeme = IfStmt.TryParse(lexemes, out IfStmt sif);
if (sif != null)
{
resultNode = sif;
return(nextLexeme);
}
nextLexeme = TryParseStruct(lexemes, out Stmt stmt);
if (stmt != null)
{
resultNode = stmt;
return(nextLexeme);
}
nextLexeme = FnCall.TryParse(lexemes, out FnCall fnc);
if (fnc != null)
{
if (nextLexeme.Value.Type == LT.OP_SC)
{
resultNode = new ExprStmt <FnCall>(fnc);
return(nextLexeme.Next);
}
}
nextLexeme = ForLoop.TryParse(lexemes, out ForLoop fl);
if (fl != null)
{
resultNode = fl;
return(nextLexeme);
}
nextLexeme = WhileLoop.TryParse(lexemes, out WhileLoop wl);
if (wl != null)
{
resultNode = wl;
return(nextLexeme);
}
nextLexeme = AssignStmt.TryParse(lexemes, out AssignStmt sa);
if (sa != null)
{
resultNode = sa;
return(nextLexeme);
}
nextLexeme = ReturnStmt.TryParse(lexemes, out ReturnStmt sr);
if (sr != null)
{
resultNode = sr;
return(nextLexeme);
}
if (lexemes.Value.Type == LT.KW_BREAK)
{
if (lexemes.Next.Value.Type != LT.OP_SC)
{
throw new Exception($"Missing semicolon after break keyword at {lexemes.Value.File}:{lexemes.Value.Line}");
}
resultNode = new BreakStmt {
Token = lexemes.Value
};
return(lexemes.Next.Next);
}
if (lexemes.Value.Type == LT.KW_CONT)
{
if (lexemes.Next.Value.Type != LT.OP_SC)
{
throw new Exception($"Missing semicolon after continue keyword at {lexemes.Value.File}:{lexemes.Value.Line}");
}
resultNode = new ContinueStmt {
Token = lexemes.Value
};
return(lexemes.Next.Next);
}
return(lexemes);
}
