/// <summary>
/// Read open bracket
/// </summary>
public static bool TryProceedOpenBracket(List <BaseFormulaNode> nodes, ReadOnlySpan <char> formula, BracketCounters negativeBracketCounters, ref int index)
{
// Read unary minus
var localIndex = UnaryMinusReader.ReadUnaryMinus(nodes, formula, index, out var isNegativeLocal);
// Check out of range
if (localIndex >= formula.Length)
{
return(false);
}
// Check open bracket
if (formula[localIndex] == OPEN_BRACKET_CHAR)
{
if (isNegativeLocal)
{
AddAdditionalNodesForUnaryMinus(nodes);
}
// Add bracket
var bracket = AddOpenBracket(nodes);
// Is unary minus
if (isNegativeLocal)
{
negativeBracketCounters.CreateNewCounter();
}
else
{
negativeBracketCounters.Proceed(bracket);
}
index = localIndex;
return(true);
}
return(false);
}
/// <summary>
/// Read close bracket
/// </summary>
public static bool TryProceedCloseBracket(List <BaseFormulaNode> nodes, ReadOnlySpan <char> formula, BracketCounters negativeBracketCounters, ref int index)
{
if (formula[index] != CLOSE_BRACKET_CHAR)
{
return(false);
}
// Add bracket
var bracket = AddCloseBracket(nodes);
// If there is unary minus, we must add close bracket
if (negativeBracketCounters.Proceed(bracket))
{
AddCloseBracket(nodes);
}
return(true);
}
/// <summary>
/// Return parsed formula nodes without RPN
/// </summary>
public List <BaseFormulaNode> ParseWithoutRpn(ReadOnlySpan <char> formula)
{
var negativeBracketCounters = new BracketCounters();
var nodes = new List <BaseFormulaNode>();
for (int i = 0; i < formula.Length; i++)
{
var ch = formula[i];
if (ch.IsWhiteSpace())
{
continue;
}
if (FunctionCharReader.TryProceedFunctionChar(nodes, ch))
{
continue;
}
if (BracketReader.TryProceedOpenBracket(nodes, formula, negativeBracketCounters, ref i))
{
continue;
}
if (BracketReader.TryProceedCloseBracket(nodes, formula, negativeBracketCounters, ref i))
{
continue;
}
if (VariableReader.TryProceedBorderedVariable(nodes, formula, ref i))
{
continue;
}
if (NumberReader.TryProceedNumber(nodes, formula, ref i))
{
continue;
}
if (FunctionsReader.TryProceedFunction(nodes, formula, ref i))
{
continue;
}
if (VariableReader.TryProceedSimpleVariable(nodes, formula, ref i))
{
continue;
}
if (WordReader.TryProceedWord(nodes, formula, ref i))
{
continue;
}
if (ListReader.TryProceedList(nodes, formula, ref i))
{
continue;
}
if (OperatorReader.TryProceedOperator(nodes, formula, ref i))
{
continue;
}
}
return(nodes);
}
