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10519 :: Error: number out of range:

• AntonioFS (orginal) [2023-09-28T12:18:15+02:00] view original

  Hello. I am a new student at Nim. I find that, with the following example, it produces an overflow error on the first statement, but on the second statement it gets it right. I don't understand

  Thank you. Best regards. Antonio F.S.

  let uint64Lit: uint64 = 18446744073709551615

  echo uint64Lit

  let uint64LitBis = 18446744073709551615'u64

  echo uint64LitBis

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• PMunch (orginal) [2023-09-28T13:26:26+02:00] view original

  In the first instance Nim tries to create an int literal first, then convert it to a uint64. In the second case you're telling Nim that the number is actually a uint64 to begin with, and thus no conversion.

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• AntonioFS (orginal) [2023-09-28T14:24:57+02:00] view original

  Thank you for your response.

  In the following examples, only uint32 and uint4 produce the overflow error. Why?

  Best regards. Antonio F.S.

  let uintLit: uint = 42; let uintLitBis = 42'u

  let uint8Lit: uint8 = 255; let uint8LitBis = 255'u8

  let uint16Lit: uint16 = 65535; let uint16LitBis = 65535'u16

  let uint32Lit: uint32 = 4294967295; let uint32LitBis = 4294967295'u32

  let uint64Lit: uint64 = 18446744073709551615; let uint64LitBis = 18446744073709551615'u64

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• janAkali (orginal) [2023-09-28T15:15:54+02:00] view original

  literals larger than int32 automatically promoted to int64, otherwise they use type int (32-bit or 64-bit depending on the platform).

  int64 literals can't be converted to uint64 type. So a workaround is to specify the type of literal with 'u64 so conversion is not needed.

  Related:

  • https://github.com/nim-lang/Nim/issues/14522
  • https://github.com/nim-lang/Nim/pull/14530

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• AntonioFS (orginal) [2023-09-29T21:52:53+02:00] view original

  Hello.

  Perfectly understood.

  Thank you very much.

  Best regards.

  Antonio F.S.

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