diff options
| -rw-r--r-- | lib/pure/encodings.nim | 53 |
1 files changed, 41 insertions, 12 deletions
diff --git a/lib/pure/encodings.nim b/lib/pure/encodings.nim index 89db0a278..dcdc474ae 100644 --- a/lib/pure/encodings.nim +++ b/lib/pure/encodings.nim @@ -7,15 +7,42 @@ # distribution, for details about the copyright. # -## Converts between different character encodings. On UNIX, this uses +## Routines for converting between different character encodings. On UNIX, this uses ## the `iconv`:idx: library, on Windows the Windows API. +## +## The following example shows how to change character encodings. +runnableExamples: + 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. +runnableExamples: + 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" + import os when not defined(windows): type ConverterObj = object - EncodingConverter* = ptr ConverterObj ## can convert between two character sets + EncodingConverter* = ptr ConverterObj ## Can convert between two character sets. else: type @@ -24,8 +51,8 @@ else: dest, src: CodePage type - EncodingError* = object of ValueError ## exception that is raised - ## for encoding errors + EncodingError* = object of ValueError ## Exception that is raised + ## for encoding errors. when defined(windows): import parseutils, strutils @@ -298,7 +325,7 @@ else: importc: "iconv", importIconv.} proc getCurrentEncoding*(uiApp = false): string = - ## retrieves the current encoding. On Unix, always "UTF-8" is returned. + ## 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. when defined(windows): @@ -307,7 +334,7 @@ proc getCurrentEncoding*(uiApp = false): string = result = "UTF-8" proc open*(destEncoding = "UTF-8", srcEncoding = "CP1252"): EncodingConverter = - ## opens a converter that can convert from `srcEncoding` to `destEncoding`. + ## Opens a converter that can convert from `srcEncoding` to `destEncoding`. ## Raises `IOError` if it cannot fulfill the request. when not defined(windows): result = iconvOpen(destEncoding, srcEncoding) @@ -326,7 +353,7 @@ proc open*(destEncoding = "UTF-8", srcEncoding = "CP1252"): EncodingConverter = "cannot find encoding " & srcEncoding) proc close*(c: EncodingConverter) = - ## frees the resources the converter `c` holds. + ## Frees the resources the converter `c` holds. when not defined(windows): iconvClose(c) @@ -421,12 +448,13 @@ when defined(windows): else: convertFromWideString(codePageTo, wideString) proc convert*(c: EncodingConverter, s: string): string = - ## converts `s` to `destEncoding` that was given to the converter `c`. It - ## assumed that `s` is in `srcEncoding`. - ## utf-16BE, utf-32 conversions not supported on windows result = convertWin(c.src, c.dest, s) else: proc convert*(c: EncodingConverter, s: string): string = + ## 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. result = newString(s.len) var inLen = csize_t len(s) var outLen = csize_t len(result) @@ -467,10 +495,11 @@ else: proc convert*(s: string, destEncoding = "UTF-8", srcEncoding = "CP1252"): string = - ## converts `s` to `destEncoding`. It assumed that `s` is in `srcEncoding`. + ## 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. - ## utf-16BE, utf-32 conversions not supported on windows + ## + ## .. warning:: UTF-16BE and UTF-32 conversions are not supported on Windows. var c = open(destEncoding, srcEncoding) try: result = convert(c, s) |