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7471 :: Length of a string in bytes

• Steven (orginal) [2021-02-04T11:49:16+01:00] view original

  How do I get the length of a string in bytes?

  Thanks.

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• lqdev (orginal) [2021-02-04T11:52:18+01:00] view original

  All strings in Nim are just seq[char], so yourString.len will work. You need to use unicode.runeLen if you want unicode length.

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• DeletedUser (orginal) [2021-02-04T11:53:28+01:00] view original

  Strings are not seq[char], they are openarray[char]. If you cast strings to seqs or vice versa you will get runtime errors

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• Steven (orginal) [2021-02-04T12:13:45+01:00] view original

  Perhaps if I explain what I want to do ...

  I'm making a cgi that will create a JSONObject, I then want to return that object as a UTF8 encoded string complete with the Content-Length header

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• mratsim (orginal) [2021-02-04T12:52:22+01:00] view original

  If you do yourString.len You get the length of the string content in byte. There is an extra byte for \0 at the end of the string but that's technically not part of the content.

  I don't know if this is what Content-length expect but I would be surprise if Unicode length was used in headers.

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• lqdev (orginal) [2021-02-04T13:41:08+01:00] view original

  That's not true, while a string will indeed convert into an openArray[char], it's still a string under the hood. The memory representation for a string is internally the same as for a seq[char], so it's "safe" to use cast[seq[char]](yourString). Though I wouldn't rely on that personally.

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• arnetheduck (orginal) [2021-02-15T12:00:11+01:00] view original

  is internally the same

  almost - string adds a x00` character at the end of the bytes which is not counted - it's necessary to maintain compatibility with C - in particular, it means you can't safely cast a seq[char] to a string and a string will not quite look the same in memory as a corresponding seq[char]

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