/// <summary>
/// Create a MathNode to hold an operator
/// </summary>
/// <param name="input">Must be +, -, /, *</param>
/// <exception cref="InvalidOperationException">When supplied a string other than the OperatorConstants values in AllowedOperators.IsAnOperator</exception>
public MathNode(string input)
{
if (AllowedOperators.IsAnOperator(input))
{
Operator = input;
NodeType = Enums.NodeType.Operation;
}
else
{
throw new InvalidOperationException($"{nameof(input)} is not in the list of allowed operators (* / + -)");
}
}
/// <summary>
/// Build an array of MathNodes which either have a fraction, or an operator in them
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public static MathNode[] Parse(string[] input)
{
int elements = input.Length;
MathNode[] operations = new MathNode[elements];
for (int i = 0; i < input.Length; i++)
{
//Is it an operator>
if (AllowedOperators.IsAnOperator(input[i]))
{
operations[i] = new MathNode(input[i]);
}
//Try to handle it as a fraction
else
{
string c = CleanFraction(input[i]);
try
{
if (c.Contains(" "))
{
//Fractions library only takes care of the 1/2 part from 3 1/2
string[] split = c.Split(' ');
Fraction f1 = Fraction.FromString(split[0]);
Fraction f2 = Fraction.FromString(split[1]);
operations[i] = new MathNode(f1.Add(f2));
}
else
{
//Whole number or simple fraction
Fraction f = Fraction.FromString(c);
operations[i] = new MathNode(f);
}
}
catch (Exception e)
{
//Do some logging with e
Console.WriteLine($"Invalid fractional value {input[i]}. " + Environment.NewLine + e.Message + Environment.NewLine + e.StackTrace);
//Don't throw e or you may lose stack info, rethrow original error, probably a parse error from test values like 'bob'
throw;
}
}
}
return(operations);
}
