# std/encodings

Dark Mode

- Manual
- Standard library
- Index
- Compiler docs
- Fusion docs
- devel, stable

Search:
Source Edit

Routines for converting between different character encodings. On UNIX, this uses the iconv library, on Windows the Windows API.

The following example shows how to change character encodings.

Example:

    import std/encodings
    when defined(windows):
      let
        orig = "öäüß"
        # convert `orig` from "UTF-8" to "CP1252"
        cp1252 = convert(orig, "CP1252", "UTF-8")
        # convert `cp1252` from "CP1252" to "ibm850"
        ibm850 = convert(cp1252, "ibm850", "CP1252")
        current = getCurrentEncoding()
      assert orig == "\195\182\195\164\195\188\195\159"
      assert ibm850 == "\148\132\129\225"
      assert convert(ibm850, current, "ibm850") == orig

The example below uses a reuseable `EncodingConverter` object which is created by `open` with `destEncoding` and `srcEncoding` specified. You can use `convert` on this object multiple times.

Example:

    import std/encodings
    when defined(windows):
      var fromGB2312 = open("utf-8", "gb2312")
      let first = "\203\173\197\194\163\191\210\187" &
          "\203\242\209\204\211\234\200\206\198\189\201\250"
      assert fromGB2312.convert(first) == "谁怕？一蓑烟雨任平生"

      let second = "\211\208\176\215\205\183\200\231" &
          "\208\194\163\172\199\227\184\199\200\231\185\202"
      assert fromGB2312.convert(second) == "有白头如新，倾盖如故"

# Imports

os

# Types

    EncodingConverter = ptr ConverterObj

  Can convert between two character sets. Source Edit

    EncodingError = object of ValueError

  Exception that is raised for encoding errors. Source Edit

# Procs

    proc close(c: EncodingConverter) {....raises: [], tags: [].}

  Frees the resources the converter `c` holds. Source Edit

    proc convert(c: EncodingConverter; s: string): string {....raises: [OSError],
        tags: [].}

  Converts `s` to `destEncoding` that was given to the converter `c`. It assumes that `s` is in `srcEncoding`.
  Warning: UTF-16BE and UTF-32 conversions are not supported on Windows.
  Source Edit

    proc convert(s: string; destEncoding = "UTF-8"; srcEncoding = "CP1252"): string {.
        ...raises: [EncodingError, OSError], tags: [].}

  Converts `s` to `destEncoding`. It assumed that `s` is in `srcEncoding`. This opens a converter, uses it and closes it again and is thus more convenient but also likely less efficient than re-using a converter.
  Warning: UTF-16BE and UTF-32 conversions are not supported on Windows.
  Source Edit

    proc getCurrentEncoding(uiApp = false): string {....raises: [], tags: [].}

  Retrieves the current encoding. On Unix, "UTF-8" is always returned. The `uiApp` parameter is Windows specific. If true, the UI's code-page is returned, if false, the Console's code-page is returned. Source Edit

    proc open(destEncoding = "UTF-8"; srcEncoding = "CP1252"): EncodingConverter {.
        ...raises: [EncodingError], tags: [].}

  Opens a converter that can convert from `srcEncoding` to `destEncoding`. Raises `IOError` if it cannot fulfill the request. Source Edit