private MathTryParseResult TryParseExpression(string expression, ICollection <Variable> variables)
{
foreach (var expressionParser in _expressionParsers
.OrderByDescending(f => f is SumParser)
.ThenByDescending(f => f is ProductParser)
.ThenByDescending(f => f.Name.Length)
.ToList())
{
var parseResult = expressionParser.TryParse(expression, variables);
if (parseResult.IsSuccessfulCreated)
{
return(parseResult);
}
}
var matchedConstant = _constants
.Where(c => c.Name.ToLower() == expression)
.FirstOrDefault();
if (matchedConstant != null)
{
return new MathTryParseResult
{
IsSuccessfulCreated = true,
Expression = _numberFactory.Create(matchedConstant.Value)
}
}
;
if (variables != null && variables.Any(p => p.Name.ToLower() == expression))
{
return new MathTryParseResult
{
IsSuccessfulCreated = true,
Expression = ParseVariable(expression, variables)
}
}
;
return(new MathTryParseResult
{
IsSuccessfulCreated = false,
ErrorMessage = "Unknown Expression in expression: " + expression
});
}