"Bald Eagle" <cre### [at] netscapenet> wrote:
>
> I see where it's going wrong, and this will give you an idea of why:
>
>     #switch(true)
>
>     #case(1)
>      rgb <0, 0, 0.2>
>     #break
>
>     #case(
>        // no (strcmp(IMG_TYPE,AA), which is the only 'correct' match
>        (strcmp(IMG_TYPE,BB))
>        | (strcmp(IMG_TYPE,CC))
>      )
>
> #switch(true) is a very strange usage, and I'm sure clipka could give some
> source-code explanation of why it works the way it does.
> But basically, as I suspected, it just selects the FIRST #case() regardless of
> what it is.

But here's a very similar example (though without any ORs, which might make all
the difference), and it selects the 2nd #case (green)...

#switch(true)
#case(0)
     rgb <0, 0, 0.2> // BLUE
#break
#case(1)
    rgb <0,1,0> // GREEN
#break
....

This makes sense to me (well, at the moment, anyway!), as it looks like
#switch(true) is picking the #case with the appropriate 'true' result of (1)
>
> In fact, check out:
>
>     #switch(strcmp(IMG_TYPE,BB) | strcmp(IMG_TYPE,CC) )
>
>      #case(-10)
>      rgb <1, 1, 0>
>     #break
>
>      #case(-6)
>      rgb <1, 1, 1>
>     #break
>
>     #case(1)
>      rgb <0, 0, 0.2>
>     #break
>
>     #case(1000)
>
> It selects the blue pigment, which corresponds to 1.

*That's* a really unexpected result, IMO; neither of the #switch's strcmp()s
'match' IMG_TYPE (which would be AA), yet #case(1) is chosen as if #switch is
'true.' And looking at it in a different brain-twisting way (one that's
incorrect, no doubt), it seems that either #case(-6) or #case(-10) should be
chosen, but certainly not #case(1)

It all makes my brain hurt :-O

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