Enum member isSummary

Tests whether a struct/class has the necessary information for calculating a T-test. It must have a property .mean (mean), .stdev (stdandard deviation), .var (variance), and .N (sample size).

enum isSummary(T) = is(typeof(T.init.mean)) && is(typeof(T.init.stdev)) && is(typeof(T.init.var)) && is(typeof(T.init.N));