private Expression ParseTerm()
{
//Console.WriteLine(_enumerator.Current.Kind.ToString() + "Term");
var first = ParseFactor();
while (_enumerator.MoveNext() &&
(MatchCurrentBool(TokenKind.STAR) ||
MatchCurrentBool(TokenKind.SLASH) ||
MatchCurrentBool(TokenKind.PERCENT)))
{
var op = _enumerator.Current.Kind;
var errRow = _enumerator.Current.row;
var errCol = _enumerator.Current.column;
if (_enumerator.MoveNext())
{
var second = ParseFactor();
first = new BinOp(first.Row,
first.Column,
op,
first,
second
);
}
else
{
throw new SyntaxException($"Expected token at {errRow}:{errCol}", errRow, errCol);
}
}
//Console.WriteLine(first.GetType().ToString());
return(first);
}
private Expression ParseExpr()
{
//Console.WriteLine(_enumerator.Current.Kind.ToString() + "Expr");
var first = ParseTerm();
while (
MatchCurrentBool(TokenKind.PLUS) ||
MatchCurrentBool(TokenKind.MINUS))
{
var op = _enumerator.Current.Kind;
var ErrRow = _enumerator.Current.row;
var ErrCol = _enumerator.Current.column;
if (_enumerator.MoveNext())
{
var second = ParseTerm();
first = new BinOp(first.Row,
first.Column,
op,
first,
second
);
}
}
if (MatchCurrentBool(TokenKind.IF) && _enumerator.MoveNext())
{
var condition = ParseExpr();
MatchCurrent(TokenKind.ELSE);
_enumerator.MoveNext();
var elseExpression = ParseExpr();
return(new ConditionalExpression(first.Row,
first.Column,
first,
condition,
elseExpression));
}
if (MatchCurrentBool(TokenKind.LESS) ||
MatchCurrentBool(TokenKind.GREATER) ||
MatchCurrentBool(TokenKind.EQEQUAL) ||
MatchCurrentBool(TokenKind.GREATEREQUAL) ||
MatchCurrentBool(TokenKind.LESSEQUAL))
{
var op = _enumerator.Current.Kind;
if (_enumerator.MoveNext())
{
var third = ParseExpr();
first = new BinOp(first.Row,
first.Column,
op,
first,
third
);
}
}
if (MatchCurrentBool(TokenKind.CIRCUMFLEX))
{
var op = _enumerator.Current.Kind;
if (_enumerator.MoveNext())
{
var fourth = ParseExpr();
first = new BinOp(first.Row,
first.Column,
op,
first,
fourth
);
}
}
//first.PrintOp(0);
return(first);
}
