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8711 :: How would this endianness check be translated to Nim?

• xigoi (orginal) [2021-12-14T12:19:45+01:00] view original

  I've been sent the following C code by a friend:

  #define IS_BIG_ENDIAN (*(uint16_t *)"\0\xff" < 0x100)
  Run

  I'm wondering how the same would be written in Nim. Note that I know about std/endians, I'm just curious about the translation of this particular snippet. I tried:

  let isBigEndian = cast[uint16]([0x00'u8, 0xff'u8]) < 0x100
  echo isBigEndian
  Run

  It seems to work correctly, but I'm curious if it's actually correct and if there's a better way to write it.

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• PMunch (orginal) [2021-12-14T12:23:44+01:00] view original

  That check should be equivalent. The original goes through a pointer deref, but I don't think that should matter.

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• Araq (orginal) [2021-12-14T14:02:18+01:00] view original

  The correct way to do is is to use: system.cpuEndian == bigEndian

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