public static NumberExprPart ConsumeInput(Queue <char> input)
{
ExprPartsMemory.RecursionLevel++;
if (!input.TryDequeue(out var c))
{
throw new UnexpectedEndOfInputException();
}
if (c.IsOpeningBracket())
{
var memory = new ExprPartsMemory();
memory.AddLast(ConsumeInput(input));
return(new EndOfSubExpr(memory).ConsumeInput(input));
}
if (c.IsPartOfNumber())
{
return(new Number(new ExprPartsMemory(), c.ToString()).ConsumeInput(input));
}
if (c.IsPrefixOperator())
{
return(new PrefixOperator(new ExprPartsMemory(), c).ConsumeInput(input));
}
throw new InvalidCharacterSequenceException(c, ExprPartsMemory.InputLength - input.Count);
}
public PrefixOperator(ExprPartsMemory memory, char op)
{
this.memory = memory;
this.op = op;
}
public EndOfSubExpr(ExprPartsMemory memory)
{
this.memory = memory;
}
public NonPrefixOperator(ExprPartsMemory memory, char op)
{
this.memory = memory;
this.memory.AddLast(SupportedOperators.OperatorsTable[op]);
}
public Number(ExprPartsMemory memory, string head)
{
this.memory = memory;
currentExprPartBuilder = new StringBuilder(head);
}
// this exists only for better understanding of code, so we can clearly see the endpoint of the expr parsing
public static NumberExprPart GetResult(ExprPartsMemory memory)
{
return(memory.GetResult());
}
