```
milovidov-desktop :) SELECT -1::INT

Syntax error: failed at position 10 ('::')
```
{
    
    
    ASTPtr expr_node;
    ASTPtr start_node;
    ASTPtr length_node;
    if (!ParserKeyword("SUBSTRING").ignore(pos, expected))
        return false;
    if (pos->type != TokenType::OpeningRoundBracket)
        return false;
    ++pos;
    if (!ParserExpression().parse(pos, expr_node, expected))
        return false;
    if (pos->type != TokenType::Comma)
    {
        if (!ParserKeyword("FROM").ignore(pos, expected))
            return false;
    }
    else
    {
        ++pos;
    }
    if (!ParserExpression().parse(pos, start_node, expected))
        return false;
    if (pos->type == TokenType::ClosingRoundBracket)
    {