[m-users.] STATE_VARIABLE_IO_0 has instantiatedness ddgame.m:042: mostly_unique

[emacstheviking]

...but I can't see what I have done wrong!!!! I have this in my graphics
window: the intenttion is to create an SDL window and render and then hand
back the graphics state and yes or no, making the basic_window `det`.

:- pred basic_window(
    string::in, int::in, int::in, int::in, int::in,
    gfx_state::in, {gfx_state, bool}::out,
    io::di, io::uo) is det.

basic_window(Title, X, Y, W, H, GIn, {GOut, yes}, !IO) :-
    sdl_createwindow(Title, X, Y, W, H, [resizable], yes(Wnd), !IO),
    sdl_createrenderer(Wnd, -1, [accelerated], yes(_), !IO),
    GOut = GIn ^ gfx_wnd := maybe.yes(Wnd).

basic_window(Title, X, Y, W, H, GIn, {GIn, no}, !IO).

And calling it from my "execute" predicate int he game controller....

:- pred execute(gfx_state::in, io::di, io::uo) is det.

execute(GfxState, !IO) :-
    (
        basic_window("blah", 0, 0, 400, 200, GfxState, {GfxState1, yes},
!IO)
    ->
        random.init(0, RS),
        sdl_getticks(TNow, !IO),
        starfield.init(100, Starfield, RS, RS0),

        AppState  = app_state(
            TNow,
            GfxState1,
            Starfield
        ),
        game_loop(AppState, RS0, !IO)
    ;
        format("basic window failed\n", [], !IO)
    ),
    format("*\n* All over\n*\n", [], !IO).

But on building it I get this and I cannot figure out my error!






*ddgame.m:042: In clause for `execute(in, di, uo)':ddgame.m:042:   in
argument 8 of call to predicate `gfx.basic_window'/9:ddgame.m:042:   mode
error: variable `STATE_VARIABLE_IO_0' has instantiatednessddgame.m:042:
`mostly_unique',ddgame.m:042:   expected instantiatedness was `unique'.*

I can't figure out what "mostly" is doing there...how did the compiler get
to that place ?
TIA
Sean
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