time dmd -c -o- -version=A -I$code main.d 0.16s
time dmd -c -o- -version=B -I$code main.d 0.01s ---main.d: module tests.private_import.main; import tests.private_import.fun; void test(){} --- ---fun.d: module tests.private_import.fun; version(A) import std.datetime; //version(C) private import std.datetime; void foo(){ // same as version(C) if this feature were implemented version(B) import std.datetime; } ---