/// <summary>
///
/// </summary>
/// <param name="first"></param>
/// <returns></returns>
public static EXPRESSION parse(Token first, iSCOPE context)
{
return(LOGICAL.parse(first, context));
}
public static new EXPRESSION parse(Token first, iSCOPE context)
{
EXPRESSION result = RELATIONAL.parse(first, context);
if (result == null)
{
return(null);
}
Span begin = result.span;
while (true)
{
Token token = get();
switch (token.code)
{
case TokenCode.Ampersand:
case TokenCode.AmpAmp:
case TokenCode.Vertical:
case TokenCode.VertVert:
forget(); break;
case TokenCode.Identifier:
Category cat = new Category(CategoryCode.operatorr);
if (token.image == "or")
{
forget(); Token second = get();
if (second.code == TokenCode.Else)
{
forget();
token = new Token(new Span(token, second), TokenCode.Vertical, "or else", cat);
}
else
{
token = new Token(token.span, TokenCode.VertVert, "or", cat);
}
break;
}
else if (token.image == "and")
{
forget(); Token second = get();
if (second.code == TokenCode.Then)
{
forget();
token = new Token(new Span(token, second), TokenCode.Ampersand, "and then", cat);
}
else
{
token = new Token(token.span, TokenCode.AmpAmp, "and", cat);
}
break;
}
else
{
goto Out;
}
default:
goto Out;
}
EXPRESSION right = RELATIONAL.parse(null, context);
result = new LOGICAL(token, result, right);
result.setSpan(begin, right.span);
}
Out:
return(result);
}