What is wrong with this boilerplate mixin?

[AF]

Hello,

 To make Win programming simpler, I divided sample application
(winsample.d) in a standard module (modwin.d) containing the
boilerplate code, and a application (appwin.d) file.
 Both files resides in the same directory.
 However, it does not link:

 D:\temp\dlang5>dmd appwin.d
c:\dmd\bin\..\..\dm\bin\link.exe appwin,,,user32+kernel32/noi;
OPTLINK (R) for Win32  Release 7.50B1
Copyright (C) Digital Mars 1989 - 2001  All Rights Reserved

c:\dm\bin\..\lib\SNN.lib(winstart)
 Error 42: Symbol Undefined _WinMain at 16

 So, what to do? And, 2nd, could things be made simpler? Attached
are modwin.d and appwin.d.
begin 644 appwin.d
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M#0H-"FUI>&EN(%=I;D%P<#L-"@T*#0II;G0@;7E7:6Y-86EN*$A)3E-404Y#
M12!H26YS=&%N8V4L2$E.4U1!3D-%(&A0<F5V26YS=&%N8V4L3%!35%(@;'!#
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M+BXN(&EN<V5R="!U<V5R(&-O9&4@:&5R92`N+BX@*B\-"B`@("!R971U<FX@
%,#L-"GT`
`
end
begin 644 modwin.d
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M:70H*3L-"F5X=&5R;B`H0RD@=F]I9"!?;6]D=6QE0W1O<B at I.PT*97AT97)N
M("A#*2!V;VED(%]M;V1U;&5$=&]R*"D[#0IE>'1E<FX@*$,I('9O:60 at 7VUO
M9'5L955N:71497-T<R at I.PT*#0IT96UP;&%T92!7:6Y!<'`H*0T*>PT*"65X
M=&5R;B`H5VEN9&]W<RD-"@EI;G0 at 5VEN36%I;BA(24Y35$%.0T4@:$EN<W1A
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M*BEO+G1O4W1R:6YG*"DL(")%<G)O<B(L#0H)"0D@("`@34)?3TL@?"!-0E])
M0T].15A#3$%-051)3TXI.PT*"0ER97-U;'0@/2`P.PD)+R\@9F%I;&5D#0H)
M("`@('T-"@D-"@D@("`@9V-?=&5R;2 at I.PD)"2\O(')U;B!F:6YA;&EZ97)S
M.R!T97)M:6YA=&4 at 9V%R8F%G92!C;VQL96-T;W(-"@D@("`@<F5T=7)N(')E
,<W5L=#L-"@E]#0I]
`
end