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Am 19.04.2014 23:18 schröbte Sean Conner:

It was thus said that the Great Coroutines once stated:

I think what you have there is a compound literal, bro: &(int){1}


   Ah, thanks.  I couldn't remember the name of the concept.


Actually a nice concept. Helps with defining type-safe integer typedefs ...




   I also love <stdint.h> and <stdbool.h>.  The former replaces a large block
of preprocessor code I used to use to get known sized integers, and the
later gives me booleans, true and false (okay, so booleans are a bit larger
than 1 bit, but hey, I can live with that).


I think we all wish booleans were 1-bit for memory concerns, but
accessing word-sized primitives is much faster -- which is why it's
traditionally defined as an int.


   GCC uses a byte to store a bool.  But if C had restricted taking the
address of a bool (which I doubt could be done in practice) then maybe it
could have gone with bit-packing bools.
What about arrays of bools (which implicitly convert to pointer to first element), or passing a pointer to bool so that you can modify it? Not to mention that you probably would save space anyway, because of padding and alignment requirements. 




I find myself doing this even if 'bool' does exist because I have to
write code for both WIndows, sometimes Solaris, and the non-fucky
platforms:

typedef int boolean;

#if true
#elseif
#    define true 1
#endif

#if false
#elseif
#    define false 0
#endif


That would break if someone defined `false` to be 0.



   I tend to define those values as:

#ifndef FALSE
#  define FALSE 0
#endif

#ifndef TRUE
#  define TRUE !FALSE
#endif

   I felt it was a bit safer that way, because in C, true is anything other
than 0.


I assume you know by now that `!FALSE` is exactly the same as `1` ...
The only sane pre-C99 choice is *not* to define TRUE (the nice thing about C99's _Bool is that there are only two values). 



   -spc



Philipp