/// <summary>
/// Returns TRUE if the given <paramref name="expression"/> contains a textual TDIL extension function invocation.
/// If so, the out parameters <paramref name="match"/> describes the match of the regular expression and
/// <paramref name="function"/> describes the function to invoke.
/// </summary>
/// <param name="expression">Expression to check</param>
/// <param name="match">Found match. May be NULL</param>
/// <param name="function">Identified function. May be NULL</param>
/// <returns>TRUE if a function invocation has been found</returns>
private bool IsFunctionInvocation(string expression, out Match match, out TdilExtensionFunctionInfo function)
{
List <TdilExtensionFunctionInfo> functionTable = _extensionFunctionRegistry._functionTable;
function = null;
match = null;
if (string.IsNullOrEmpty(expression))
{
return(false);
}
string trdExpr = expression.Trim('\"');
if (string.IsNullOrEmpty(trdExpr))
{
return(false);
}
for (int i = -1; ++i != functionTable.Count;)
{
TdilExtensionFunctionInfo funcInfo = functionTable[i];
Match regexMatch = Regex.Match(expression, funcInfo.RegularExpression);
if (regexMatch.Success)
{
function = funcInfo;
match = regexMatch;
return(true);
}
}
return(false);
}
/// <summary>
/// Replaces the given <paramref name="match"/> within the containing <paramref name="expression"/>
/// with the given <paramref name="function"/> invocation.
/// </summary>
/// <param name="expression">Expression that contains the match</param>
/// <param name="match">Match of a function invocation</param>
/// <param name="function">Function that is being called</param>
/// <returns></returns>
private string AdjustFunctionCall(string expression, Match match, TdilExtensionFunctionInfo function)
{
string resultFormat = function.ResultFormat;
// Process function arguments
TdilExtensionFunctionArgumentInfo[] arguments = function.Arguments;
for (int i = -1; ++i != arguments.Length;)
{
TdilExtensionFunctionArgumentInfo argument = arguments[i];
string argName = argument.Name;
Group matchGroup = match.Groups[argName];
string adjustment = SelectAdjustmentValue(argument.Adjustment);
string replacement = SelectReplacement(matchGroup.Success,
matchGroup.Value, adjustment, argument.DefaultValue);
resultFormat = resultFormat.Replace(argName, replacement);
}
// Update expression
string expr = expression.Replace(match.Value, resultFormat);
// Remove leading and trailing quotes
string trmdExpr = expr.Trim('\"');
return(trmdExpr);
}
/// <summary>
/// Adds the given <paramref name="functionInfo"/> to the registry.
/// </summary>
/// <param name="functionInfo">Function to add</param>
public void Add(TdilExtensionFunctionInfo functionInfo)
{
_functionTable.Add(functionInfo);
}
