A short summary of the calculation of a Min
- No mediation (Exception!)
var min = result.Partials.Where(o => o.IsPositive).Min(o => o.Result);
This is your case: if there are no matching elements, then the Min
call will raise an exception (InvalidOperationException
).
- With DefaultIfEmpty()
-- still troublesome
var min = result.Partials.Where(o => o.IsPositive)
.Select(o => o.Result)
.DefaultIfEmpty()
.Min();
DefaultIfEmpty
will create an enumeration over the 0 element, when there are no elements in the list. How do you know that 0 is the Min
or if 0 stands for a list with no elements?
- Nullable values; A better solution
var min = result.Partials.Where(o => o.IsPositive)
.Min(o => (decimal?)o.Result);
Here Min
is either null (because that's equal to default(decimal?)
) or the actual Min
found.
So a consumer of this result will know that:
- When result is
null
then the list had no elements
- When the result is a decimal value then the list had some elements and the
Min
of those elements is that returned value.
However, when this doesn't matter, then min.GetValueOrDefault(0)
can be called.
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