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12924 :: variable declaration check

• ajaychat3 (orginal) [2025-05-14T11:05:22+02:00] view original

  I am facing a strange issue with variable declaration in nim. The program is like this.

  
  var
      cStatus_P,c_GEN: int
  
  cGen = 13;
  cStatus_P = 14;
  
  echo c_gen
  Run

  When I run this program, no error is thrown for cGen not being declared but cGEN is using the value of c_GEN.

  
  nim c   --w:on --opt:speed --d:release --hints:off --passC:-ffast-math --mm:orc  -r  "Var_Decl_Test.nim" (in directory: E:\Work\IFRS17\CreditAccess\Mar_25\Workbook)
  13
  Compilation finished successfully.
  Run

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• moigagoo (orginal) [2025-05-14T11:15:56+02:00] view original

  In Nim, c_gen, cGen, cgen, and c_GEN are equivalent identifiers. But C_gen, CGen, Cgen, or C_GEN would be a different identifier.

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• moigagoo (orginal) [2025-05-14T11:19:01+02:00] view original

  https://nim-lang.org/docs/manual.html#lexical-analysis-identifier-equality

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• crfout (orginal) [2025-05-14T11:19:47+02:00] view original

  Nim identifiers explicitly ignore underscores and case for anything other than the first character. This is a basic feature of the language. c_GEN == c_gen == cGen == cgen == c_G_e_N

  https://nim-lang.org/docs/manual.html#lexical-analysis-identifier-equality

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• ajaychat3 (orginal) [2025-05-14T11:21:17+02:00] view original

  Thanks. Is there a way to disable this equivalence and treat them as different?

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• nrk (orginal) [2025-05-14T11:27:37+02:00] view original

  I don't think so.

  What you can do is to pass --styleCheck:usages --styleCheck:hint, and then the compiler will complain when you use a symbol with the incorrect name.

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• ajaychat3 (orginal) [2025-05-14T11:33:55+02:00] view original

  Thanks everyone for clarifying. I was not aware of this identifier equivalence. @nrk. The compiler option seems to provide a hint about symbol mismatch but still executes with default functionality. Thanks

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• nrk (orginal) [2025-05-14T11:49:27+02:00] view original

  Yes, that's what I meant.

  If you want to stop execution, you can use styleCheck:error too. Personally I prefer hints so that a new compiler version won't break compilation outright if it changes in what it's reporting (which has happened before). But I guess that's only relevant if you want to support multiple compiler versions.

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• ajaychat3 (orginal) [2025-05-14T15:52:52+02:00] view original

  @nrk Thanks again

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