Name: Modifications to Eval() function.
Based on AutoIt Source code: 3.0.103
Version: 2 (backwards compatible)

In Script_misc.cpp:
------------------

///////////////////////////////////////////////////////////////////////////////
// Eval()
// 2005-01-16 Modified by S.A.Pechler; Added Expression evaluation.
///////////////////////////////////////////////////////////////////////////////

AUT_RESULT AutoIt_Script::F_Eval(VectorVariant &vParams, Variant &vResult)
{
	bool			bConst = false;
	VectorToken		LineTokens;				// Vector of tokens from parameter
	uint			iPos;					// Position in Vector

 	if (g_oVarTable.isDeclared(vParams[0].szValue()))
 	{
 		Variant *pvTemp;
 		g_oVarTable.GetRef(vParams[0].szValue(), &pvTemp, bConst);
 		vResult = *pvTemp;
 		return AUT_OK;
 	}
 	else
 	{
		// Expression did not contain a declared variable. 
		// Check if it contains a valid expression.

		// NOTE: the lexer has changed not peeking into the cache when line=0 is given!
		if ( AUT_FAILED(Lexer(0, vParams[0].szValue(), LineTokens) ) ) // First convert the string parameter into tokens
		{
			SetFuncErrorCode(1);	// Silent error 
			vResult = "";
			return AUT_OK;			// Lexer failed, but we won't report it visually
		}

		// Now parse the newly created tokens
		// To stay compatible with the pre-3.0.103 eval() versions we must now check if somebody 
		// passed an undefined variable name. Like: Eval("doesnotexist") 
		// In this case the line has only two tokens, and that's of type 'userfunction' and TOK_END 
		// (that's what the Lexer returns when he doesn't know what it is)

		if (LineTokens.size() > 1)		// Be sure they didn't pass an empty string
			if (!((LineTokens.size() == 2) && (LineTokens[0].m_nType == TOK_USERFUNCTION)))   // inverted boolean
			{	
				iPos = 0;  // First token position
				if ( AUT_SUCCEEDED( Parser_EvaluateCondition(LineTokens, iPos, bConst) ) ) 
				{
					vResult = bConst;
					return AUT_OK;
				}
			}
 	}
	SetFuncErrorCode(1);		// Silent error
	vResult = "";
	return AUT_OK; 
} // Eval()


In script_lexer.cpp:
-------------------

	// 16-01-2005 SvenP: MODIFIED; if linenumber = 0 then don't check the cache (->eval function!)

	if ((nCacheIdx >0 ) && (m_LexerCache[nCacheIdx].nLineNum == nLineNum))