/// <summary>
/// Extracts the body of the given preprocessor directive symbol, parses it, and returns the parsed expression.
/// </summary>
/// <param name="parser">The C# parser.</param>
/// <param name="sourceCode">The source code containing the preprocessor directive symbol.</param>
/// <param name="preprocessorSymbol">The preprocessor directive symbol.</param>
/// <param name="startIndex">The index of the start of the expression body within the text string.</param>
/// <returns>Returns the expression.</returns>
internal static Expression GetConditionalPreprocessorBodyExpression(
CsParser parser, SourceCode sourceCode, Symbol preprocessorSymbol, int startIndex)
{
Param.AssertNotNull(parser, "parser");
Param.AssertNotNull(sourceCode, "sourceCode");
Param.AssertNotNull(preprocessorSymbol, "preprocessorSymbol");
Param.AssertGreaterThanOrEqualToZero(startIndex, "startIndex");
Debug.Assert(preprocessorSymbol.SymbolType == SymbolType.PreprocessorDirective, "The symbol is not a preprocessor directive.");
string text = preprocessorSymbol.Text.Substring(startIndex, preprocessorSymbol.Text.Length - startIndex).Trim();
if (text.Length > 0)
{
using (StringReader reader = new StringReader(text))
{
// Extract the symbols within this text.
CodeLexer lexer = new CodeLexer(parser, sourceCode, new CodeReader(reader));
List<Symbol> symbolList = lexer.GetSymbols(sourceCode, null);
SymbolManager directiveSymbols = new SymbolManager(symbolList);
CodeParser preprocessorBodyParser = new CodeParser(parser, directiveSymbols);
// Parse these symbols to create the body expression.
return preprocessorBodyParser.GetNextConditionalPreprocessorExpression(sourceCode);
}
}
// The directive has no body.
return null;
}
internal static Expression GetConditionalPreprocessorBodyExpression(CsParser parser, SourceCode sourceCode, Symbol preprocessorSymbol, int startIndex)
{
string s = preprocessorSymbol.Text.Substring(startIndex, preprocessorSymbol.Text.Length - startIndex).Trim();
if (s.Length > 0)
{
StringReader code = new StringReader(s);
CodeLexer lexer = new CodeLexer(parser, sourceCode, new CodeReader(code));
SymbolManager symbols = new SymbolManager(lexer.GetSymbols(sourceCode, null));
CodeParser parser2 = new CodeParser(parser, symbols);
return parser2.GetNextConditionalPreprocessorExpression(sourceCode);
}
return null;
}