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13488 :: Type mismatch with bitOr on distinct type

• hmf (orginal) [2025-11-01T17:58:24+01:00] view original

  I am a nim-lang newbie using the nim-glfw and trying to compile:

  
  glClear(bitor(GL_COLOR_BUFFER_BIT, GL_DEPTH_BUFFER_BIT))
  Run

  which gives me the following error:

  
      triangle_0.nim(153, 18) Error: type mismatch
          ... Expression: bitor(16384'u, 256'u)
          ...   [1] 16384'u: GLbitfield
          ...   [2] 256'u: GLbitfield
          ... Expected one of (first mismatch at [position]):
          ... [1] macro bitor[T: SomeInteger](x, y: T; z: varargs[T]): T
          ...
  Run

  The parameter type and its values are defined as:

  
      GLbitfield* = distinct uint32
      GL_DEPTH_BUFFER_BIT* = 0x00000100.GLbitfield
      GL_STENCIL_BUFFER_BIT* = 0x00000400.GLbitfield
      GL_COLOR_BUFFER_BIT* = 0x00004000.GLbitfield
  Run

  What is the correct way of doing bit twiddling on this distinct type?

  TIA

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• nrk (orginal) [2025-11-01T19:09:05+01:00] view original

  How about:

  
  glClear(GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT)
  Run

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• dwhall256 (orginal) [2025-11-01T20:21:54+01:00] view original

  Look up the borrow pragma in the manual

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• hmf (orginal) [2025-11-01T21:08:36+01:00] view original

  @nrk Thanks. That compiles. I did not realize it, but the operator is defined in the code. It uses a borrow. I was under the impression that the or is not for bit manipulation in version 2.

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• hmf (orginal) [2025-11-01T21:11:01+01:00] view original

  @dwhall256 I was aware of this. I was assuming I could not define these myself. Thanks.

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• dwhall256 (orginal) [2025-11-02T03:54:06+01:00] view original

  Also, the keyword or maps to the bitwise OR operation when the arguments are integers. Strictly for understanding Nim a little more, it could be written with type conversions like this:

  
  glClear(GLbitfield(GL_COLOR_BUFFER_BIT.uint32 or GL_DEPTH_BUFFER_BIT.uint32)))
  Run

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• hmf (orginal) [2025-11-02T08:59:27+01:00] view original

  @dwhall256 Thanks. Understood. The .borrow. makes for a cleaner solution, but this is good to know.

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