Kenji Hara:
AFAIK, there is no plan for fix. The behavior is currently a part of language design.
Considering matters of D semantic uniformity, and the code shown by Dicebot:
template Hello(T...) if (T.length == 1) { static if (is(T[0])) // ... else // ... } Then maybe the current behavior is worth reconsidering. Bye, bearophile