Re: [PATCH 001/112] ALSA: add snd_pcm_is_playback/capture() macro

Hi Sakamoto-san

...

+#define snd_pcm_is_playback(x) _Generic((x), \

•  int			: snd_pcm_direction_is_playback, \
  

• unsigned int : snd_pcm_direction_is_playback, \
• unsigned char : snd_pcm_direction_is_playback, \
• unsigned short : snd_pcm_direction_is_playback, \

•      struct snd_pcm_substream *: snd_pcm_substream_is_playback, \
  

• const struct snd_pcm_substream *: snd_pcm_substream_is_playback)(x)

(snip)

In my opinion, it is not so important to distinguish some types which can be converted to integer implicitly/explicitly in the above case. The 'default' association is available in such case, like:

+#define snd_pcm_is_playback(x) _Generic((x), \

•      struct snd_pcm_substream *: snd_pcm_substream_is_playback, \
  

• const struct snd_pcm_substream *: snd_pcm_substream_is_playback, \

•                         default: snd_pcm_direction_is_playback)(x)
  
  

The association would match [u|i][8|16|32|64] and f[32|64] types, and would not match to any type of pointers. However, it depends on your preference.

Wow ! I didn't know _Generic() can use default, and more good things is that it could handle bit-field, too!! It is perfect.

Thank you for your help !!

Best regards --- Kuninori Morimoto