/// <summary>
///
/// </summary>
/// <param name="currentPos">结束后指向该Token的下一个字符处</param>
/// <param name="end"></param>
/// <param name="matched">
/// string: 已处理转义符
/// var: 不含$符，即matched就是变量名
/// int, float, operator: 不变
/// </param>
/// <returns></returns>
private MatchTokenResult MatchToken(int currentPos, int end)
{
//string matched = null;
MatchTokenResult result = new MatchTokenResult();
result.BeginPos = currentPos;
for (; isWhiteSpace(expr[result.BeginPos]) && result.BeginPos < end; result.BeginPos++) ;
if (result.BeginPos >= end)
{
result.EndPos = result.BeginPos;
result.TokenType = TokenType.Null;
return result;
}
result.EndPos = result.BeginPos;
char c = expr[result.EndPos];
switch (c)
{
case '+':
case '-':
case '*':
case '/':
case '^':
case '(':
case ')':
result.Matched = c.ToString();
result.EndPos++;
result.TokenType = TokenType.Operator;
return result;
case '=':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.Matched = "==";
result.EndPos += 2;
}
else
{
result.Matched = "=";
result.EndPos++;
}
result.TokenType = TokenType.Operator;
return result;
case '!':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.Matched = "!=";
result.EndPos += 2;
}
else
{
result.Matched = "!";
result.EndPos++;
}
result.TokenType = TokenType.Operator;
return result;
case '&':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '&')
{
result.Matched = "&&";
result.EndPos += 2;
result.TokenType = TokenType.Operator;
return result;
}
else
{
kernel.IssueError(ErrorType.UnknownToken, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return result;
}
case '|':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '|')
{
result.Matched = "||";
result.EndPos += 2;
result.TokenType = TokenType.Operator;
return result;
}
else
{
kernel.IssueError(ErrorType.UnknownToken, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return result;
}
case '>':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.Matched = ">=";
result.EndPos += 2;
}
else
{
result.Matched = ">";
result.EndPos ++;
}
result.TokenType = TokenType.Operator;
return result;
case '<':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.EndPos += 2;
result.Matched = "<=";
}
else
{
result.EndPos++;
result.Matched = "<";
}
result.TokenType = TokenType.Operator;
return result;
case '"':
result.EndPos++;
if (result.EndPos >= end)
{
kernel.IssueError(ErrorType.SingleQuote, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return result;
}
StringBuilder matchedBuilder = new StringBuilder();
bool escape = false;
while (result.EndPos < end)
{
if (expr[result.EndPos] == '\\')
{
if(escape)
{
matchedBuilder.Append('\\');
escape = false;
}
else
{
escape = true;
}
}
else if (expr[result.EndPos] == '"')
{
if (escape)
{
matchedBuilder.Append('"');
escape = false;
}
else
{
break;
}
}
else
{
if (escape)
{
switch (expr[result.EndPos])
{
case 'n':
matchedBuilder.Append('\n');
break;
case 't':
matchedBuilder.Append('\t');
break;
case 'r':
matchedBuilder.Append('\r');
break;
default:
kernel.IssueError(ErrorType.UnknownEscapeChar, loc.Offset(result.EndPos), expr[result.EndPos].ToString());
result.TokenType = TokenType.Error;
return result;
}
escape = false;
}
else
{
matchedBuilder.Append(expr[result.EndPos]);
}
}
result.EndPos++;
}
if (result.EndPos < end) //遇到引号后跳出while
{
result.EndPos++; //跳过引号
result.Matched = matchedBuilder.ToString();
result.TokenType = TokenType.String;
return result;
}
else //遇到End而跳出while,即没有配对引号
{
kernel.IssueError(ErrorType.SingleQuote, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return result;
}
default:
string substr = expr.Substring(result.EndPos, end - result.EndPos);
Match m;
if ((m = floatPattern.Match(substr)).Success)
{
result.Matched = m.Groups[0].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Float;
return result;
}
else if ((m = intPattern.Match(substr)).Success)
{
result.Matched = m.Groups[0].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Int;
return result;
}
else if ((m = varPattern.Match(substr)).Success)
{
result.Matched = m.Groups[1].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Variable;
return result;
}
else if ((m = boolPattern.Match(substr)).Success)
{
result.Matched = m.Groups[0].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Bool;
return result;
}
else
{
kernel.IssueError(ErrorType.UnknownToken, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return result;
}
}
}
/// <summary>
///
/// </summary>
/// <param name="currentPos">结束后指向该Token的下一个字符处</param>
/// <param name="end"></param>
/// <param name="matched">
/// string: 已处理转义符
/// var: 不含$符，即matched就是变量名
/// int, float, operator: 不变
/// </param>
/// <returns></returns>
private MatchTokenResult MatchToken(int currentPos, int end)
{
//string matched = null;
MatchTokenResult result = new MatchTokenResult();
result.BeginPos = currentPos;
for (; isWhiteSpace(expr[result.BeginPos]) && result.BeginPos < end; result.BeginPos++)
{
;
}
if (result.BeginPos >= end)
{
result.EndPos = result.BeginPos;
result.TokenType = TokenType.Null;
return(result);
}
result.EndPos = result.BeginPos;
char c = expr[result.EndPos];
switch (c)
{
case '+':
case '-':
case '*':
case '/':
case '^':
case '(':
case ')':
result.Matched = c.ToString();
result.EndPos++;
result.TokenType = TokenType.Operator;
return(result);
case '=':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.Matched = "==";
result.EndPos += 2;
}
else
{
result.Matched = "=";
result.EndPos++;
}
result.TokenType = TokenType.Operator;
return(result);
case '!':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.Matched = "!=";
result.EndPos += 2;
}
else
{
result.Matched = "!";
result.EndPos++;
}
result.TokenType = TokenType.Operator;
return(result);
case '&':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '&')
{
result.Matched = "&&";
result.EndPos += 2;
result.TokenType = TokenType.Operator;
return(result);
}
else
{
kernel.IssueError(ErrorType.UnknownToken, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return(result);
}
case '|':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '|')
{
result.Matched = "||";
result.EndPos += 2;
result.TokenType = TokenType.Operator;
return(result);
}
else
{
kernel.IssueError(ErrorType.UnknownToken, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return(result);
}
case '>':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.Matched = ">=";
result.EndPos += 2;
}
else
{
result.Matched = ">";
result.EndPos++;
}
result.TokenType = TokenType.Operator;
return(result);
case '<':
if (result.EndPos + 1 < end && expr[result.EndPos + 1] == '=')
{
result.EndPos += 2;
result.Matched = "<=";
}
else
{
result.EndPos++;
result.Matched = "<";
}
result.TokenType = TokenType.Operator;
return(result);
case '"':
result.EndPos++;
if (result.EndPos >= end)
{
kernel.IssueError(ErrorType.SingleQuote, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return(result);
}
StringBuilder matchedBuilder = new StringBuilder();
bool escape = false;
while (result.EndPos < end)
{
if (expr[result.EndPos] == '\\')
{
if (escape)
{
matchedBuilder.Append('\\');
escape = false;
}
else
{
escape = true;
}
}
else if (expr[result.EndPos] == '"')
{
if (escape)
{
matchedBuilder.Append('"');
escape = false;
}
else
{
break;
}
}
else
{
if (escape)
{
switch (expr[result.EndPos])
{
case 'n':
matchedBuilder.Append('\n');
break;
case 't':
matchedBuilder.Append('\t');
break;
case 'r':
matchedBuilder.Append('\r');
break;
default:
kernel.IssueError(ErrorType.UnknownEscapeChar, loc.Offset(result.EndPos), expr[result.EndPos].ToString());
result.TokenType = TokenType.Error;
return(result);
}
escape = false;
}
else
{
matchedBuilder.Append(expr[result.EndPos]);
}
}
result.EndPos++;
}
if (result.EndPos < end) //遇到引号后跳出while
{
result.EndPos++; //跳过引号
result.Matched = matchedBuilder.ToString();
result.TokenType = TokenType.String;
return(result);
}
else //遇到End而跳出while,即没有配对引号
{
kernel.IssueError(ErrorType.SingleQuote, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return(result);
}
default:
string substr = expr.Substring(result.EndPos, end - result.EndPos);
Match m;
if ((m = floatPattern.Match(substr)).Success)
{
result.Matched = m.Groups[0].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Float;
return(result);
}
else if ((m = intPattern.Match(substr)).Success)
{
result.Matched = m.Groups[0].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Int;
return(result);
}
else if ((m = varPattern.Match(substr)).Success)
{
result.Matched = m.Groups[1].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Variable;
return(result);
}
else if ((m = boolPattern.Match(substr)).Success)
{
result.Matched = m.Groups[0].Value;
result.EndPos += m.Length;
result.TokenType = TokenType.Bool;
return(result);
}
else
{
kernel.IssueError(ErrorType.UnknownToken, loc.Offset(result.EndPos));
result.TokenType = TokenType.Error;
return(result);
}
}
}
