/// <summary>
/// Handler for 1 or more construct
/// </summary>
/// <param name="separator">the separator token between items</param>
/// <param name="terminal">the ending token</param>
/// <param name="meth">the method to call to parse an item</param>
/// <param name="result">the parsed expression</param>
/// <returns>true if match parsed, false otherwise</returns>
private bool ReadAhead(Token separator, Token terminal, ExpressionMethod meth, out Expression result)
{
Token tok = PeekToken();
result = null;
if (tok == terminal)
{
ReadToken();
return false;
}
else if (tok == separator)
{
ReadToken();
}
result = meth();
return true;
}
/// <summary>
/// Asserts that the token read is the one expected
/// </summary>
/// <param name="expected">the expected token</param>
/// <param name="actual">the actual token</param>
/// <param name="message">message to use in the exception if expected != actual</param>
private static void RequireToken(Token expected, Token actual, string message)
{
if (actual != expected)
{
throw new ParseException(message + " Expected: " + expected + " got: " + actual);
}
}
/// <summary>
/// Test the token to see if its a quoted string
/// </summary>
/// <param name="tok">the token to test</param>
/// <returns>true if its a quoted string</returns>
private static bool IsQuotedString(Token tok)
{
return tok.type == TokenType.DoubleQuotedString || tok.type == TokenType.SingleQuotedString;
}
/// <summary>
/// Test the token to see if its a keyword
/// </summary>
/// <param name="tok">the token to test</param>
/// <returns>true if its a keyword</returns>
private static bool IsKeyword(Token tok)
{
// include null?
return tok.type == TokenType.Identifier && tok.value == "new";
}
/// <summary>
/// Test the token to see if its an identifier
/// </summary>
/// <param name="tok">the token to test</param>
/// <returns>true if its an identifier</returns>
private static bool IsIdentifier(Token tok)
{
return tok.type == TokenType.Identifier;
}
private bool Equals(Token other)
{
return type == other.type && value == other.value;
}