/////// test.d //////
import std.format;

void main()
{
    format!"%f"([1]);
}
/////////////////////

Currently produces:

.../std/format/package.d(748): Error: expression `FormatException(['I', 'n', 'c', 'o', 'r', 'r', 'e', 'c', 't', ' ', 'f', 'o', 'r', 'm', 'a', 't', ' ', 's', 'p', 'e', 'c', 'i', 'f', 'i', 'e', 'r', ' ', 'f', 'o', 'r', ' ', 'r', 'a', 'n', 'g', 'e', ':', ' ', '%', 'f'], ".../std/format/internal/write.d", 1722LU, null, null, 0u)` is not constant
.../std/format/package.d(1370):        while evaluating: `static assert(!e)`
test.d(5): Error: template instance `std.format.format!("%f", int[])` error instantiating