Mailman 3 November 2006 - lxml - The Python XML Toolkit

[lxml-dev] etree.XSLTApplyError: xsltValueOf: text copy failed (Custom XSLT function usage error)
by Chas Emerick Nov. 15, 2006

Nov. 15, 2006

One of the key features of lxml from our perspective is the stated availability of custom function bindings within xslt. However, we've run into some difficulty in implementing them. Here's a concise example. First, we set up our custom function, nothing special: >>> from lxml import etree as ET >>> ns = ET.FunctionNamespace(None) >>> ns['testfunction'] = lambda dummy, *args: 'function args: %s' % str(args) Next, we put together a really simple xml document -- and we can see that calling this custom function within direct XPath calls works just fine: >>> doc = ET.parse(StringIO('<p style="margin-top:5px">Normal <b>BOLD</b> text</p>')) >>> doc.xpath('testfunction(5, 4, 3, 2, 1, "some string")') "function args: (5.0, 4.0, 3.0, 2.0, 1.0, 'some string')" >>> doc.xpath('testfunction(//b)') 'function args: ([<Element b at 11d2058>],)' >>> doc.xpath('testfunction(//*)') 'function args: ([<Element p at 11d24e0>, <Element b at 11d2058>],)' Now, we come to our trouble: calling the custom function from within an XSLT stylesheet: >>> ET.XSLT(ET.parse(StringIO(''' <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"> <xsl:output method="xml"/> <xsl:template match="*"> <x> <xsl:value-of select="testfunction(.)"/> </x> </xsl:template> </xsl:stylesheet> ''')))(doc) Traceback (most recent call last): File "<stdin>", line 1, in ? File "xslt.pxi", line 445, in etree.XSLT.__call__ etree.XSLTApplyError: xsltValueOf: text copy failed I found a mention of this error being related to libxslt not accepting the results of xpath expressions as arguments into custom functions (<http://www.stylusstudio.com/xsllist/200604/ post40310.html>). However, calling the custom function from within the stylesheet using numeric literals also fails: >>> ET.XSLT(ET.parse(StringIO(''' <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"> <xsl:output method="xml"/> <xsl:template match="*"> <elt> <xsl:value-of select="testfunction(5, 6)"/> </elt> </xsl:template> </xsl:stylesheet>''')))(doc) Traceback (most recent call last): File "<stdin>", line 1, in ? File "xslt.pxi", line 445, in etree.XSLT.__call__ etree.XSLTApplyError: xsltValueOf: text copy failed ---------------- Any thoughts? I have a hunch that we're just missing something simple (perhaps in setting up the function namespace and the function binding, but it seems like we're following the examples in the docs pretty closely). FYI, this is in python 2.4, with lxml 1.1.2. Thanks much, Chas Emerick Founder, Snowtide Informatics Systems Enterprise-class PDF content extraction cemerick(a)snowtide.com http://snowtide.com | +1 413.519.6365

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[lxml-dev] Installing lxml on Windows
by Javier de la Torre Nov. 5, 2006

Nov. 5, 2006

Hi all, I am trying to install lxml on Windows, well, what I actually want is to create a windows python installation that includes lxml already installed on it. I have created a Python program that make use of lxml and I would like to distribute it for Windows as an installer. My idea is to install Python and all requiered libraries for my software on it and then bundle this python folder together with my program. I am trying to install lxml in Windows and I dont manage. Following the instructions that appear on the lxml website seems that I have to download the binaries for lxml, libxslt, etc and lace it somewhere, I imagine that in the windows folder, but would be possible to have all this in the python folder and that lxml make use of them? I just want to avoid users of my program to download from 10 different places Python and non-Python programs in order to use my app. Thanks for any suggestion. Javier.

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[lxml-dev] Windows binaries
by Javier de la Torre Nov. 4, 2006

Nov. 4, 2006

Hi, I have now a more general question. Is there a Windows binary for lxml that includes libxml and libxslt as an easy installer? In http:// cheeseshop.python.org/pypi/lxml I only find linux packages for py2.4 and 2.5. I will be happy also with a no so new version. Thanks. Javier.

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[lxml-dev] I get CDATA inside parsed html <script> element, and can not retrieve it's text
by Alexander Kozlovsky Nov. 3, 2006

Nov. 3, 2006

Hello all! I'm very new with lxml. Probably, I find a bug. AFAIK, lxml does not expose direct interface to CDATA sections. But, when I use etree.HTML function I get content of <script> as CDATA section! >>> html = etree.HTML('<script> alert("Hello!"); </script>') >>> etree.tostring(html) '<html><head><script><![CDATA[ alert("Hello!"); ]]></script></head></html>' The problem is, I cannot retrieve content of <script> tag because lxml does not allow this: >>> script = html.find('.//script') >>> len(script) 0 >>> print script.text None EXPECTED: >>> print script.text alert("Hello!"); Is it really a bug, or I don't understand something? -- Best regards, Alexander mailto:alexander.kozlovsky@gmail.com

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[lxml-dev] Can't build on Windows
by Dan Posluns Nov. 1, 2006

Nov. 1, 2006

I'm not normally a Windows user so I'm at my wit's end here trying to get lxml to install. When I try easy_install I get the following: C:\Python24\Scripts>easy_install lxml Searching for lxml Reading http://www.python.org/pypi/lxml/ Reading http://codespeak.net/lxml Reading http://www.python.org/pypi/lxml/1.1.2 Best match: lxml 1.1.2 Downloading http://codespeak.net/lxml/lxml-1.1.2.tgz Processing lxml-1.1.2.tgz Running lxml-1.1.2\setup.py -q bdist_egg --dist-dir c:\docume~1\dposluns\locals~ 1\temp\easy_install-vc3ufv\lxml-1.1.2\egg-dist-tmp-vxzlya Building lxml version 1.1.2 warning: no files found matching 'etree.c' under directory 'src\lxml' warning: no files found matching 'objectify.c' under directory 'src\lxml' warning: no files found matching 'etree.h' under directory 'src\lxml' warning: no files found matching 'etree_defs.h' under directory 'src\lxml' warning: no files found matching 'pubkey.asc' under directory 'doc' warning: no previously-included files found matching 'doc\pyrex.txt' warning: no previously-included files found matching 'src\lxml\etree.pxi' cl : Command line warning D4025 : overriding '/W3' with '/w' cl : Command line warning D4029 : optimization is not available in the standard edition compiler etree.c c:\Documents and Settings\dposluns\Local Settings\Temp\easy_install-vc3ufv\lxml- 1.1.2\src\lxml\etree_defs.h(20) : fatal error C1083: Cannot open include file: ' libxml/xmlversion.h': No such file or directory error: Setup script exited with error: command '"C:\Program Files\Microsoft Visu al Studio .NET 2003\Vc7\bin\cl.exe"' failed with exit status 2 When I try David Sankel's technique to build the libraries statically, I manage to get as far as adding wsock32 (which took me long enough to figure out how to do - again, not a Windows programmer) before the build process borked out on me with the same errors. I was using the Windows distributions of libxml, libxslt, iconv and zlib from zlatkovic.com. Can anyone help me figure this one out? Thanks, Dan. -- Dan Posluns, B. Eng. & Scty. (Software Engineering and Society) dan(a)danposluns.com - ICQ: 35758902 http://www.danposluns.com "The great thing about being the only species on the planet that makes a distinction between right and wrong is that we get to make the rules up for ourselves as we go." - Douglas Adams, Last Chance to See

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