On Thursday, 12 December 2013 at 11:39:56 UTC, FreeSlave wrote: > I guess alias also should include extern(C) declaration i.e. > the right way is > alias Tcl_InterpDeleteProc = extern(C) void function(ClientData > clientData, Tcl_Interp* interp) nothrow; Unfortunately that syntax doesn't compile. The alternative does however.