diff options
author | William S Fulton <wsf@fultondesigns.co.uk> | 2015-12-19 03:52:33 +0000 |
---|---|---|
committer | William S Fulton <wsf@fultondesigns.co.uk> | 2015-12-19 03:55:26 +0000 |
commit | 01611702ec04fa70445fd2c7d37b9b312d3f7561 (patch) | |
tree | 94118fe116503d25354f9603e873c4aae743c8bc /Doc | |
parent | 291186cfaf39497a42f6ed6395ddaeb2b466ed04 (diff) | |
download | swig-01611702ec04fa70445fd2c7d37b9b312d3f7561.tar.gz |
Python 2 Unicode strings can be used as inputs to char * or std::string types
Requires SWIG_PYTHON_2_UNICODE to be defined when compiling generated code.
Diffstat (limited to 'Doc')
-rw-r--r-- | Doc/Manual/Contents.html | 1 | ||||
-rw-r--r-- | Doc/Manual/Python.html | 66 |
2 files changed, 67 insertions, 0 deletions
diff --git a/Doc/Manual/Contents.html b/Doc/Manual/Contents.html index 21ba6eaad..6d2cdaa76 100644 --- a/Doc/Manual/Contents.html +++ b/Doc/Manual/Contents.html @@ -1598,6 +1598,7 @@ <li><a href="Python.html#Python_nn75">Buffer interface</a> <li><a href="Python.html#Python_nn76">Abstract base classes</a> <li><a href="Python.html#Python_nn77">Byte string output conversion</a> +<li><a href="Python.html#Python_2_unicode">Python 2 Unicode</a> </ul> </ul> </div> diff --git a/Doc/Manual/Python.html b/Doc/Manual/Python.html index 962ee6843..c5219b693 100644 --- a/Doc/Manual/Python.html +++ b/Doc/Manual/Python.html @@ -122,6 +122,7 @@ <li><a href="#Python_nn75">Buffer interface</a> <li><a href="#Python_nn76">Abstract base classes</a> <li><a href="#Python_nn77">Byte string output conversion</a> +<li><a href="#Python_2_unicode">Python 2 Unicode</a> </ul> </ul> </div> @@ -6163,6 +6164,71 @@ For more details about the <tt>surrogateescape</tt> error handler, please see <a href="https://www.python.org/dev/peps/pep-0383/">PEP 383</a>. </p> +<H3><a name="Python_2_unicode"></a>36.12.5 Python 2 Unicode</H3> + + +<p> +A Python 3 string is a Unicode string so by default a Python 3 string that contains Unicode +characters passed to C/C++ will be accepted and converted to a C/C++ string +(<tt>char *</tt> or <tt>std::string</tt> types). +A Python 2 string is not a unicode string by default and should a Unicode string be +passed to C/C++ it will fail to convert to a C/C++ string +(<tt>char *</tt> or <tt>std::string</tt> types). +The Python 2 behavior can be made more like Python 3 by defining +<tt>SWIG_PYTHON_2_UNICODE</tt> when compiling the generated C/C++ code. +By default when the following is wrapped: +</p> + +<div class="code"><pre> +%module unicode_strings +char *charstring(char *s) { + return s; +} +</pre></div> + +<p> +An error will occur when using Unicode strings in Python 2: +</p> + +<div class="targetlang"><pre> +>>> from unicode_strings import * +>>> charstring("hi") +'hi' +>>> charstring(u"hi") +Traceback (most recent call last): + File "<stdin>", line 1, in ? +TypeError: in method 'charstring', argument 1 of type 'char *' +</pre></div> + +<p> +When the <tt>SWIG_PYTHON_2_UNICODE</tt> macro is added to the generated code: +</p> + +<div class="code"><pre> +%module unicode_strings +%begin %{ +#define SWIG_PYTHON_2_UNICODE +%} + +char *charstring(char *s) { + return s; +} +</pre></div> + +<p> +Unicode strings will be successfully accepted and converted from UTF-8, +but note that they are returned as a normal Python 2 string: +</p> + +<div class="targetlang"><pre> +>>> from unicode_strings import * +>>> charstring("hi") +'hi' +>>> charstring(u"hi") +'hi' +>>> +</pre></div> + </body> </html> |