2.4.2 (February 8th, 2010)
  • Fix issue where subclasses of Template failed to pick up attributes in the searchlist
  • Remove old/outdated bundled memcached python client
  • Allow for #encoding directives to exist after a comment (i.e. not the first line in a module)
  • Remove support for WebWare servlets (which caused significant performance slowdowns on Mac OS X)
  • Old/stale code pruned in preparation for Python 3 support
2.4.1 (December 19th, 2009)
  • –quiet flag added to cheetah to silence printing to stdout (abbeyj)
  • Refactoring to minimize the amount of forked code for Python3 (rtyler)
  • Template.compile() will no longer create class names with numerous leading underscores (rtyler; reported by Kirill Uhanov)
  • DirectiveAnalyzer (cheetah-analyze script) added to report directive usage in templates (rtyler)
  • Older LaTeX docs converted to rst for Sphinx (rtyler)
  • Prevent #raw blocks from evaluating $-placeholders and escaped strings (karmix0)
  • New tests added to verify PSP behavior and other untested internals (rtyler)
2.4.0 (October 24th, 2009)
  • Fix a major performance regression in Template.__init__()
  • More graceful handling of unicode when calling .respond() to render a template
  • Minor code updates
  • Update the default filter (thanks mikeb!)
2.3.0 (October 24th, 2009) (loosely equivalent to 2.4.0)
  • Fix a major performance regression in Template.__init__()
  • More graceful handling of unicode when calling .respond() to render a template
  • Minor code updates
  • Update the default filter (thanks mikeb!)
2.2.2 (September 10th, 2009)
  • Prevent _namemapper.c from segfaulting when PyImport_ImportModule fails for some reason (Bogdano Arendartchuk <debogdano@gmail.com>)
  • Removal of the contrib/markdown module (in favor of a setuptools dependency)
  • Default setup.py to use setuptools by default, failing that, fall back to distutils
  • Improvements to setup.py to support building for Windows (thanks abbeyj!)
  • Improvements to C-based NameMapper for Windows
  • Fixes for a swath of unit tests on Windows
  • Re-enabling the EOL tests (whoops)
  • Fix for unicode/utf-8 dynamic compilation error (thanks mikeb!) (Test.Unicode.JBQ_UTF8_Test8)
  • 0000010: [Templates] Failure to execute templates on Google App Engine (rtyler)
  • 0000026: [Compiler] Support multiple inheritance (rtyler)
2.2.1 (June 1st, 2009)
  • 0000020: [Templates] Builtin support for using Cheetah with Django (rtyler)
  • 0000021: [Compiler] @static and @classmethod don’t properly define the _filter local (rtyler)
  • 0000023: [Compiler] Update Template super calls to use super() (rtyler)
  • Update all references to communitycheetah.org to point back at cheetahtemplate.org
2.2.0 (May 17th, 2009)
  • Switch all internal representations of template code to unicode objects instead of str() objects
  • Convert unicode compiled template to an utf8 char buffer when writing to a file (Jean-Baptiste Quenot <jbq@caraldi.com>)
  • 0000011: [Templates] Calling a function with arguments calls the function with None (rtyler)
  • 0000015: [Tests] Resolve test failures in ‘next’ branch (rtyler)
  • 0000019: [Templates] Properly warn when joining unicode and non-unicode objects in DummyTransaction (rtyler)
2.1.2 (May 5, 2009)
  • 0000006: [Templates] Support @staticmethod and @classmethod (rtyler)
2.1.1 (April 16, 2009)
  • Support __eq__() and __ne__() the way you might expect in src/Tools/RecursiveNull (patch suggested by Peter Warasin <peter@endian.com>)
  • Applied patch to avoid hitting the filesystem to get the file modification time everytime a #include directive is processed (Jean-Baptiste Quenot <jbq@caraldi.com>)
  • Applied patch to fix some annoying cases when Cheetah writes to stderr instead of propagating the exception (Jean-Baptiste Quenot <jbq@caraldi.com>)
  • Added KDE editor support
  • Applied patch to correct importHook behavior on Python 2.6 (reported/patched by Toshio Ernie Kuratomi <a.badger@gmail.com>)
  • Correct unicode issue when calling/embedding unicode templates inside of other templtes (testcase Tests.Unicode.JPQ_UTF8_Test3. reported by Jean-Baptiste Quenot <jbq@caraldi.com>)
  • Added –shbang option (e.g. “cheetah compile –shbang ‘#!/usr/bin/python2.6’ “)
  • Removed dependency on optik OptionParser in favor of builtin Python optparse module
  • Introduction of the #transform directive for whole-document filtering
  • Introduction of Cheetah.contrib.markdown and Cheetah.Filters.Markdown for outputting a markdown processed template (meant for #transform)
  • Cheetah.Filters.CodeHighlighter, pygments-based code highlighting filter for use with #transform
  • Addition of “useLegacyImportMode” compiler setting (defaulted to True) to allow for older (read: broken) import behavior (March 27, 2009)
  • Fix inline import issue introduced in v2.1.0
2.1.0 (March 16, 2009)
  • Quiet DeprecationWarnings being printed to stderr when using Cheetah on Python 2.6 and up. Patch suggested by Satoru SATOH <satoru.satoh@gmail.com>
  • Apply patch to support parallel compilation of templates courtesy of Evan Klitzke <evan@eklitzke.org>
  • Corrected issue when __getattr__ calls on searchList objects raise exceptions (tyler@slide.com)
  • make autocalling in valueForName correctly ignore newstyle classes and instances that are callable, as it does for oldstyle classes and instances. Patch from lucas@endian.com [TR]
  • made it possible to chain multiple decorators to a method #def [TR with patch from Graham Dennis]
  • fixed a bug in _eatMultiLineDef that Graham Dennis reported. [TR]
  • fixed ‘module.__init__() argument 1 must be string, not unicode’ bug in Template.py reported by Erwin Ambrosch [TR]
2.0.1 (Nov 16, 2007)
  • fixed a deadlock Christoph Zwerschke found in Cheetah.ImportHooks. [TR]
2.0 (Oct 12, 2007)


  • fixed exception handling issue in the C implemenation of NameMapper [patch from Eric Huss]
  • fixed filtering of #included subtemplates [patch from Brian Bird]

See the release notes from 2.0b1-5 and 2.0rc1-8 for other changes since Cheetah 1.0.

2.0rc8 (April 11, 2007)


  • added a ‘#unicode <encoding>’ directive to indicate that the output of the template should be a unicode string even if the template source is a normal byte string.

    • #unicode and #encoding are mutually exclusive. Use one or the other.

    • #unicode must be on a line by itself.

    • Strings in embedded code must be explictly marked as unicode if they contain non-ascii chars:

      #unicode latin-1
      \$f(u"<some non-ascii char>") ## right
      \$f("<some non-ascii char>") ## wrong

      However, this works fine:

      #unicode latin-1
      blah blah <some non-ascii char> blah blah
  • fixed several unicode bugs in the compiler.

  • fixed some unicode issues in the standard filters.

  • fixed a few minor bugs in code that never gets called. Thanks to Alejandro Dubrovsky for pointing them out.

  • make RawOrEncodedUnicode the baseclass of all filters and remove some unused/redudant filters

  • added new compiler setting ‘addTimestampsToCompilerOutput’. See Brian Bird’s post about it. He stores his cheetah generated .py files in subversion and needed to disable the timestamp code so svn wouldn’t care when he recompiles those .py modules.

  • added the #super directive, which calls the method from the parent class which has the same as the current #def or #block method:

    #def foo
        ... child output
        #super  ## includes output of super(<CurrentClass>, self).foo()
        ... child output
    #end def
    #def bar(arg)
        ... child output
        #super(arg)  ## includes output of super(<CurrentClass>, self).bar(arg)
         ... child output
    #end def
  • added some unit tests for the new directives

2.0rc7 (July 4, 2006)


  • extended the #implements directive so an arguments list can be declared in the same fashion as #def and #block.

  • made the parser raise ParseError when $*placeholder, $*5*placeholder, $(placeholder), etc. are found within expressions. They are only valid in top-level text.

  • tweaked the parser so it’s possible to place a comment on the same line as a directive without needing to explicitly close the directive first. This works regardless of whether or not you added a colon:

    self.verify("#if 1:\\n\$aStr\\n#end if\\n",
    self.verify("#if 1:   \\n\$aStr\\n#end if\\n",
    self.verify("#if 1: ##comment \\n\$aStr\\n#end if\\n",
    self.verify("#if 1 ##comment \\n\$aStr\\n#end if\\n",

    Previously, that last test would have required an extra # to close the #if directive before the comment directive started:

    self.verify("#if 1 ###comment \\n\$aStr\\n#end if\\n",

    Code that makes use of explicit directive close tokens immediately followed by another directive will still work as expected: #if test##for i in range(10)# foo $i#end for##end if

  • safer handling of the baseclass arg to Template.compile(). It now does the right thing if the user passes in an instance rather than a class.

ImportHooks: [TR]

  • made it possible to specify a list of template filename extentions that are looped through while searching for template modules. E.g.:

    import Cheetah.ImportHooks

Core changes by MO:

  • Filters are now new-style classes.
  • WebSafe and the other optional filters in Filters.py now use RawOrEncodedUnicode instead of Filter as a base class. This allows them to work with Unicode values containing non-ASCII characters.
  • User-written custom filters should inherit from RawOrEncodedUnicode and call the superclass .filter() instead of str(). str() as of Python 2.4.2 still converts Unicode to string using ASCII codec, which raises UnicodeEncodeError if it contains non-ASCII characters.
2.0rc6 (Feb 4, 2006)


  • added a Cheetah version dependency check that raises an assertion if a template was compiled with a previous version of Cheetah whose templates must be recompiled.

  • made the Cheetah compilation metadata accessible via class attributes in addition to module globals

  • major improvement to exception reporting in cases where bad Python syntax slips past the Cheetah parser:

    File "/usr/lib/python2.4/site-packages/Cheetah/Template.py", line 792, in compile
         raise parseError
     Error in the Python code which Cheetah generated for this template:
     invalid syntax (DynamicallyCompiledCheetahTemplate.py, line 86)
     Line|Python Code
     84  |
     85  |        write('\\n\\n')
     86  |        for i an range(10): # generated from line 4, col 1
     87  |            _v = i # '\$i' on line 5, col 3
     88  |            if _v is not None: write(_filter(_v, rawExpr='\$i')) # from line 5, col 3.
     89  |            write('\\n')
     Here is the corresponding Cheetah code:
     Line 4, column 1
     Line|Cheetah Code
     2   |#compiler useNameMapper=False
     3   |
     4   |#for i an range(10)
     5   |  \$i
     6   |#end for
     7   |
2.0rc5 (Feb 3, 2006)


  • fixed a memory leak in Template.compile(), reported by Andrea Arcangeli
  • simplified concurrency locking and compile caching in Template.compile()

The command line tool (CheetahWrapper.py):

  • added new option –settings for supplying compiler settings
  • added new option –templateAPIClass to replace the environment var CHEETAH_TEMPLATE_CLASS lookup I added in 2.0b1
2.0rc4 (Jan 31, 2006)


  • fixed a typo-bug in the compile hashing code in Template.compile()
  • improved the macros framework and made it possible to implement macros in Python code so they can be shared between templates
  • more work on the #i18n directive. It’s now a macro directive.
  • added new Cheetah.Macros package
  • more tests
2.0rc3 (Jan 29, 2006)


  • added short-form single line versions of all directives that have an #end tag, except for #errorCatcher:

    #if, #else, #elif, #unless,
    #for, #while, #repeat,
    #try, #except, #finally,
    #cache, #raw
    #call, #capture

    The #def and #block directives already had single-line versions:

    #if cond: foo
    #elif cond2: bar
    #else: blarg
    #for i, val in enumerate(vals): \$i-\$val

    Note that if you accidentally leave a colon at the end of one of these directives but nothing else follows it, aside from whitespace, the parser will treat it as a normal multi-line directive.

    The first leading space after the colon is discarded. Any additional spaces will be included in the output.

    Also note, if you use the short form versions of #if/#else/#elif you must it for all three. The following is not valid:

    #if cond: foo
    #elif cond2
    #else: blarg
  • added support for $!silentModePlaceholders. This is the same as quiet mode in Velocity: http://jakarta.apache.org/velocity/docs/user-guide.html#Quiet%20Reference%20Notation

  • added support for function/method @decorators. It also works with blocks. As in vanilla Python, the @decorator statement must be followed with a function/method definition (i.e. #def or #block):

    #from xxx import aDecorator
    #def func
    #end def
    #def singleLineShortFormfunc: foo
    #block func2
    #end block
  • added a new callback hook ‘handlerForExtendsDirective’ to the compiler settings. It can be used to customize the handling of #extends directives. The callback can dynamically add import statements or rewrite the baseclass’ name if needed:

    baseClassName = handler(compiler, baseClassName)

    See the discussion on the mailing list on Jan 25th for more details.

  • changed the default filter to the one that doesn’t try to encode Unicode It was ‘EncodeUnicode’ and is now ‘RawOrEncodedUnicode’.

  • added optional support for parsing whitespace between the directive start token (#) and directive names, per Christophe Eymard’s request. For the argument behind this see the mailing list archives for Jan 29th. This is off by default. You must turn it on using the compiler setting allowWhitespaceAfterDirectiveStartToken=True:

    #for \$something in \$another
    #  for \$somethin2 in \$another2
          blahblah \$something in \$something2
    #  end for
    #end for
  • made the handling of Template.compile()’s preprocessors arg simpler and fixed a bug in it.

  • fixed attribute name bug in the .compile() method (it affected the feature that allows generated module files to be cached for better exception tracebacks)

  • refactored the #cache/CacheRegions code to support abitrary backend cache data stores.

  • added MemcachedCacheStore, which allows cache data to be stored in a memcached backend. See http://www.linuxjournal.com/article/7451 and http://www.danga.com/memcached/. This is only appropriate for systems running many Python server processes that need to share cached data to reduce memory requirements. Don’t bother with this unless you actually need it. If you have a limited number of Python server processes it is much faster, simpler, and more secure to just cache in the memory of each process.

    KEEP MEMCACHED’S LIMITED SECURITY IN MIND!! It has no authentication or encryption and will introduce a gaping hole in your defenses unless you are careful. If you are caching sensitive data you should take measures to ensure that a) untrusted local system users cannot connect to memcached server, b) untrusted external servers cannot connect, and c) untrusted users on trusted external servers cannot connect. Case (a) can be dealt with via iptable’s owner match module for one way to do this: “iptables -A … -m owner …” Cases (b) and (c) can be handled by tunnelling memcached network connections over stunnel and implementing stunnel authentication with mandatory peer/client certs.

  • some under-the-hood refactoring of the parser

  • made it possible to add custom directives, or customize the parsing/handling of existing ones, via the compiler settings ‘directiveNamesAndParsers’ and ‘endDirectiveNamesAndHandlers’

  • added a compile-time macro facility to Cheetah. These macros are very similar to macros in Lisp: http://www.apl.jhu.edu/~hall/Lisp-Notes/Macros.html.

    As with Lisp macros, they take source code (Cheetah source) as input and return source code (again Cheetah source) as output. They are executed at compile-time, just like in Lisp and C. The resultant code gets executed at run-time.

    The new #defmacro directive allows users to create macros inside the source of their templates. Macros can also be provided via the compiler setting ‘macroDirectives’. The ‘macroDirectives’ setting allows you to share common macros between templates.

    The syntax for the opening tag of #defmacro is the same as for #def and #block. It expects a macro name followed by an optional argument list in brackets. A src argument is automatically added to the beginning of every macro’s argument list. The value of the src is the block of input source code that is provided during a macro call (see below):

    #defmacro <macroname>[(argspec)]
    #end defmacro

    All of Cheetah’s syntax is available for use inside macros, but the placeholderStartToken is @ instead of $ and the directiveStartToken/EndToken is % instead of #. Any syntax using the standard $/# tokens will be treated as plain text and included in the output of the macro.

    Here are some examples:

    #defmacro addHeaderFooter
    #end defmacro
    #defmacro addHeaderFooter(header='h', footer='f')
    #end defmacro

    There is a single-line short form like for other directives:

    #defmacro addHeaderFooter: header @src footer
    #defmacro addHeaderFooter(header='h', footer='f'): @header @src @footer

    The syntax for calling a macro is similar to the simplest usage of the #call directive:

      Source \$code to wrap
    #end addHeaderFooter
    #addHeaderFooter: Source \$code to wrap
    #addHeaderFooter header='header', footer='footer: Source \$code to wrap
    In Elisp you write
    (defmacro inc (var)

    (list ‘setq var (list ‘1+ var)))

    to define the macro inc and write

    (inc x)

    which expands to

    (setq x (1+ x))

    In Cheetah you’d write

    #defmacro inc: #set @src +=1 #inc: $i

    which expands to

    #set $i += 1

    print Template(“””\ #defmacro inc: #set @src +=1 #set i = 1 #inc: $i $i”””).strip()==2

  • fixed some bugs related to advanced usage of Template.compile(). These were found via new unit tests. No one had actually run into them yet.

  • added the initial bits of an #i18n directive. It has the same semantics as:

    #call self.handleI18n
      Some \$var cheetah source
    #end call

    but has a simpler syntax:

      Some \$var cheetah source
    #end i18n
    ## single-line short form:
    #i18n: Some \$var cheetah source

    The method it calls, self.handleI18n, is just a stub at the moment, but it will soon be a wrapper around gettext. It currently has one required positional argument message. I anticipate supporting the following optional arguments:

    id = msgid in the translation catalog
    domain = translation domain
    source = source lang
    target = a specific target lang
    comment = a comment to the translation team
    plural = the plural form of the message
    n = a sized argument to distinguish between single and plural forms

    #i18n is executed at runtime, but it can also be used in conjunction with a Cheetah preprocessor or macro (see above) to support compile time translation of strings that don’t have to deal with plural forms.

  • added Cheetah.Utils.htmlEncode and Cheetah.Utils.htmlDecode

  • more docstring text

Unit tests: [TR]

  • extended the caching tests
  • added tests for the various calling styles of Template.compile()
  • added copies of all the SyntaxAndOutput tests that use a template baseclass other than Template. This ensures that all syntax & core features work with 2.0’s support for arbitrary baseclasses.
  • added tests for all the new directives and the new single-line short forms
2.0rc2 (Jan 13th, 2006)


  • fixed some python 2.4isms that slipped in. All the tests pass with Python 2.2 now
  • added lots more docstring content in the Template class
  • made multiline comments gobble whitespace like other directives, per JJ’s request. The rather longwinded compiler setting gobbleWhitespaceAroundMultiLineComments can be used to go back to the old non-gobbling behaviour if needed.
  • added #capture directive to complement the #call directive. #call executes a region of Cheetah code and passes its output into a function call #capture executes a region of Cheetah code and assigns its output to a variable
  • extended the compile caching code in Template.compile so it works with the ‘file’ arg.
  • added cacheModuleFilesForTracebacks and cacheDirForModuleFiles args to Template.compile(). See the docstring for details.
  • misc internal refactoring in the parser
  • improved handling of keyword args in the __init__ method and fixed a potential clash between the namespaces and searchList args


  • added the source for the new Cheetah website layout/content
2.0rc1 (Jan 10, 2006)


  • made it possible nest #filter directives

  • added lots more docstring content in the Template class

  • added Template.subclass() classmethod for quickly creating subclasses of existing Cheetah template classes. It takes the same args as the .compile() classmethod and returns a template that is a subclass of the template .subclass() is called from:

    T1 = Template.compile(' foo - \$meth1 - bar\\n#def meth1: this is T1.meth1')
    T2 = T1.subclass('#implements meth1\\n this is T2.meth1')
  • added baseclass arg to Template.compile(). It simplifies the reuse of dynamically compiled templates:

    # example 1, quickly subclassing a normal Python class and using its
    #  __init__ call signature:
      dictTemplate = Template.compile('hello \$name from \$caller', baseclass=dict)
      print dictTemplate(name='world', caller='me')

    # example 2, mixing a Cheetah method into a class definition:

    class Foo(dict):
        def meth1(self):
            return 'foo'
        def meth2(self):
            return 'bar'
    Foo = Template.compile('#implements meth3\\nhello \$name from \$caller',
    print Foo(name='world', caller='me')

    A side-benefit is the possibility to use the same Cheetah source with several baseclass, as the baseclass is orthogonal to the source code, unlike the #extends directive.

  • added ‘namespaces’ as an alias for ‘searchList’ in Template.__init__

  • made it possible to pass in a single namespace to ‘searchList’, which will automatically be converted into a list.

  • fixed issue with buffering and use of #call when template is used as a

    webkit servlet

  • added Cheetah.Utils.htmlEncode and htmlDecode

The command line tool (CheetahWrapper.py):

  • changed insertion order for the –env and –pickle options so they match the commandline UI of the compiled template modules themselves [TR]
2.0b5 (Jan 7, 2006)


  • made Cheetah.Template a new-style class by inserting ‘object’ into its’ inheritance tree. Templates can now use super(), properties and all the other goodies that come with new-style classes.

  • removed the WebInputMixin by placing its one method directly in the Template class.

  • removed the SettingsManager Mixin. It wasn’t being used by anything anymore.

  • added a framework for caching the results of compilations in Template.compile(). This is on by default and protects against bad performance issues that are due to programmers misguidedly compiling templates inside tight loops. It also saves on memory usage.

  • misc attr name changes to avoid namespace pollution

  • more + improved docstrings

  • replaced the oldstyle dynamic compile hacks with a wrapper around Template.compile(). The old usage pattern Template(src) now benefits from most of the recent changes:

    Template(src).__class__ == Template.compile(src)
  • removed all the extra imports required by oldstyle dynamic compile hacks

  • converted the cheetah #include mechanism to newstyle compilation and made it more flexible

  • made the #include mechanism work with file objects in addition to file names

  • made the handling of args to Template.compile() more flexible. You can now provide defaults via class attributes.

  • made preprocessors for Template.compile() work with file arguments

  • added support for specifying a __metaclass__ on cheetah template classes

  • refactored both the class and instance initialization processes

  • improved the handling of __str__ in _assignRequiredMethodsToClass

The command line tool (CheetahWrapper.py): [TR]

  • improved error output in CheetahWrapper
  • switched fill command over to new style compile usage

Unit tests: [TR]

  • fixed format string bug in unittest_local_copy.py
2.0b4 (Jan 6, 2006)


  • fixed up parsing of target lists in for loops. This was previously limited to fairly simple target lists:

    #for (\$i, \$j) in [('aa','bb'),('cc','dd')]
    #end for"
    #for (i, j) in [('aa','bb'),('cc','dd')]
    #end for"
    #for i,(j, k) in enumerate([('aa','bb'),('cc','dd')])
    #end for"
  • refactored the class initialization process

  • improved handling of target lists in #set directive. This was previously limited to fairly simple target lists. #set i,j = [1,2] … #set $i,$j = [1,2] #set (i,j) = [1,2] … #set ($i,$j) = [1,2] #set i, (j,k) = [1,(2,3)] … #set $i, ($j,$k) = [1,(2,3)]

  • made it possible for the expressionFilter hooks to modify the code chunks they are fed. Also documented the hooks in a docstring. Thus the hooks can be used as preprocessors for expressions, ‘restricted execution’, or even enforcement of style guidelines.

  • removed cheetah junk from docstrings and placed it all in comments or __moduleVars__. Per JJ’s suggestion.

  • made it possible to nest #cache directives to any level

  • made it possible to nest #call directives to any level

Unit Tests [TR]

  • extended tests for #for directive
  • expanded tests for #set directive
  • expanded tests for #call directive
  • expanded tests for #cache directive
  • added basic tests for the new $placeholder string expressions: c’text $placeholder text’
2.0b3 (Jan 5, 2006)


  • added #yield statement

  • added ability to create nested scopes/functions via nested #def statements

  • added new #call directive and related #arg directive, per Ian Bicking’s suggestion.

  • added new expression syntax c”text $placeholder text”

    for those basic function calling cases where you just need to pass in a small bit of cheetah output as an argument:

    c'a string with \$placeholders',
    c'''a string with \$placeholders''',
    c"a string with \$placeholders",
    c"""a string with \$placeholders"""
    • They can’t contain #directives, but accept any valid $placeholder syntax except caching placeholders. Caching placeholders don’t make any sense in this context.

    • They can be used *any* place where a python expression is expected.

    • They can be nested to any depth:

      \$func(c'<li>\$var1-\$var2</li>', doSomething=True)
      \$func(content=c'<li>\$var1-\$var2</li>', doSomething=True)
      \$func(lambda x,y: c'<li>\$x-\$y</li>')
      \$func(callback=lambda x,y: c'<li>\$x-\$y</li>')
      \$func(lambda x,y: c'<li>\$x-\$y-\$varInSearchList</li>')
      \$func(c'<li>\$var1-\$var2-\$func2(c"a nested expr \$var99")</li>')
      #if \$cond then c'<li>\$var1-\$var2</li>' else c'<p>\$var1-\$var2</p>'
      #def foo(arg1=c'\$var1<span class="foo">\$var2</span>'):  blah \$arg1 blah
  • added preprocessor hooks to Template.compile() can be used for partial completion or ‘compile-time-caching’ … more details and examples coming. It’s very useful, but takes a bit of explaining.

  • added ‘#set module varName = expr’ for adding module globals. JJ’s suggestion

  • improved generated docstring notes about cached vars

  • fixed silly bug related to “”” in docstring comments and statements like this ‘#def foo: $str(“””foo”””)’. Reported by JJ.

  • changed the handling of single-line defs so that ‘#def xxx:<just whitespace>\n’ will be treated as a multi-line #def. The same applies to #block. There’s a compiler setting to turn this off if you really need empty single-line #def:’s. JJ reported that this was causing great confusion with beginners.

  • improved error message for unclosed directives, per Mike Orr’s suggestion.

  • added optional support for passing the trans arg to methods via **KWS rather than trans=None. See the discussion on the mailing list Jan 4th (JJ’s post) for details. The purpose is to avoid a positional argument clash that apparently is very confusing for beginners.

    Note that any existing client code that passing the trans arg in positionally rather than as a keyword will break as a result. WebKit does this with the .respond method so I’ve kept the old style there. You can also turn this new behaviour off by either manually including the trans arg in your method signature (see the example below) or by using the compiler setting ‘useKWsDictArgForPassingTrans’=False:

    #def manualOverride(arg1, trans=None)
      foo \$arg1
    #end def


  • made the ImportHook more robust against compilation errors during import [TR]

Install scripts: [TR]

  • added optional support for pje’s setuptools
  • added cheeseshop classifiers
  • removed out of date install instructions in __init__.py

Servlet Base Class For Webkit: [TR]

  • disabled assignment of self.application (was a webware hack)

Unit Tests: [TR]

  • unit tests for most of the new syntax elements
  • tidied up some old tests
  • misc refactoring
2.0b2 (Dec 30, 2005)


Core Changes:

  • In previous versions of Cheetah tracebacks from exceptions that were raised inside dynamically compiled Cheetah templates were opaque because Python didn’t have access to a python source file to use in the traceback:

     File "xxxx.py", line 192, in getTextiledContent
       content = str(template(searchList=searchList))
     File "cheetah_yyyy.py", line 202, in __str__
     File "cheetah_yyyy.py", line 187, in respond
     File "cheetah_yyyy.py", line 139, in writeBody
    ZeroDivisionError: integer division or modulo by zero

    It is now possible to keep the generated source code from the python classes returned by Template.compile() in a cache dir. Having these files around allows Python to include the actual source lines in tracebacks and makes them much easier to understand:

    File "/usr/local/unsnarl/lib/python/us/ui/views/WikiPageRenderer.py", line 192, in getTextiledContent
      content = str(template(searchList=searchList))
    File "/tmp/CheetahCacheDir/cheetah_yyyy.py", line 202, in __str__
      def __str__(self): return self.respond()
    File "/tmp/CheetahCacheDir/cheetah_yyyy.py", line 187, in respond
    File "/tmp/CheetahCacheDir/cheetah_yyyy.py", line 139, in writeBody
      __v = 0/0 # \$(0/0)
    ZeroDivisionError: integer division or modulo by zero

    This is turned off by default. To turn it on, do this:

    class NiceTracebackTemplate(Template):
        _CHEETAH_cacheModuleFilesForTracebacks = True
        _CHEETAH_cacheDirForModuleFiles = '/tmp/CheetahCacheDir' # change to a dirname
    templateClass = NiceTracebackTemplate.compile(src)
    # or
    templateClass = Template.compile(src,
       cacheModuleFilesForTracebacks=True, cacheDirForModuleFiles='/tmp/CheetahCacheDir')

    This only works with the new Template.compile(src) usage style!

    Note, Cheetah generated modules that are compiled on the command line have never been affected by this issue. [TR]

  • added an extra comment per $placeholder to generated python code so it is easier to grok. [TR]

2.0b1 (Dec 29, 2005)


Core Changes:

  • enabled use of any expression in ${placeholders}. See the examples I posted to the email list on Dec 12th. All use cases of the #echo directive can now be handled with ${placeholders}. This came from a suggestion by Mike Orr. [TR]

  • made it possible for templates to #extend (aka subclass) any arbitrary baseclass, including Python’s new style classes. You must either compile your classes on the command line or use the new classmethod Template.compile() as described below. The old Template(src) interface still works, provided you don’t try to use this new arbitrary baseclass stuff. See my messages to the email list for more details. [TR]

  • made it possible to create template classes dynamically, rather than just instances. See the new classmethod Template.compile(). See my messages to the email list for more details. [TR]

    klass = Template.compile(src)

  • made it easier to work with custom compiler settings, particularly from the command line tool. You can now define a subclass of Template which will compile your templates using custom compilerSettings, or even a custom compiler class, without requiring you to manually pass in your compilerSettings each time or define them in the template src itself via the #compiler directive. You can make the command line tool use your subclass by defining the environment variable CHEETAH_TEMPLATE_CLASS. It should be in the form ‘package.module:class’. See my messages to the email list for more details. [TR]

  • made it possible to pass the searchList in as an argument to #def’ined methods. This makes all lookup that occur within the scope of that method use the provided searchList rather than self._searchList. This does not carry over to other methods called within the top method, unless they explicitly accept the searchList in their signature AND you pass it to them when calling them. This behaviour can be turned off with the corresponding compilerSetting ‘allowSearchListAsMethArg’ [TR]

  • added hooks for filtering / restricting dangerous stuff in cheetah source code at compile time. These hooks can be used to enable Cheetah template authoring by untrusted users. See my messages to the email list for more details. Note, it filters expressions at parse/compile time, unlike Python’s old rexec module which restricted the Python environment at runtime. [TR]

    # Here are the relevant compiler settings: # use lower case keys here!! ‘disabledDirectives’:[], # list of directive keys, without the start token ‘enabledDirectives’:[], # list of directive keys, without the start token

    ‘disabledDirectiveHooks’:[], # callable(parser, directiveKey),

    # called when a disabled directive is found, prior to raising an exception

    ‘preparseDirectiveHooks’:[], # callable(parser, directiveKey) ‘postparseDirectiveHooks’:[], # callable(parser, directiveKey)

    ‘preparsePlaceholderHooks’:[], # callable(parser) ‘postparsePlaceholderHooks’:[], # callable(parser)

    ‘expressionFilterHooks’:[], # callable(parser, expr, exprType, rawExpr=None, startPos=None) # exprType is the name of the directive, ‘psp’, or ‘placeholder’. #all lowercase

  • added support for a short EOLSlurpToken to supplement the #slurp directive. It’s currently re.compile(‘#\s*\n’) (i.e # followed by arbitrary whitespace and a new line), but this is not set in stone. One other suggestion was the backslash char, but I believe Python’s own interpretation of backslashes will lead to confusion. The compiler setting ‘EOLSlurpToken’ controls this. You can turn it off completely by setting ‘EOLSlurpToken’ to None. See the email list for more details. [TR]

  • added ‘_CHEETAH_’ prefix to all instance attribute names in compiled templates. This is related to the arbitrary baseclass change. [TR]

  • shifted instance attribute setup to _initCheetahAttributes() method. This is related to the arbitrary baseclass change. [TR]

  • made it possible to use full expressions in the #extends directive, rather than just dotted names. This allows you to do things like this:

    #from xx.TemplateRepository import getTemplateClass #extends getTemplateClass(‘someName’)

    I don’t expect this to be used much. I needed it for a wiki system in which the baseclasses for the templates are dynamically compiled at run time and are not available via simple imports. [TR]

  • added compiler setting autoImportForExtendDirective=True, so this existing default behaviour can be turned off when needed. [TR]

  • fixed a bug in the parsing of single-line #def’s and #block’s when they are enclosed within #if … #end if. Reported by Marcin Gajda [TR]

  • tweak to remove needless write(‘’) calls in generated code [TR]

The command line tool (CheetahWrapper.py):

  • added code to cleanup trailing slashes on path arguments (code originally from Mike Orr) [TR]
  • turned on the ImportHooks by default for the ‘cheetah fill’ command. See the discussion on the email list [TR]


  • fixed a name error bug in the ImportHooks [TR]
1.0 (Dec 4, 2005)


Version bump from 1.0rc3

1.0rc3 (Nov 30, 2005)


  • added useSearchList compiler setting [TR] This defaults to True, but if false, the compiler assumes the first portion of a $variable (before the first dot) is a global, builtin, or local var that doesn’t need looking up in the searchlist. NameMapper’s unified dotted notation will still be used on the rest of the lookup (provide the setting useNameMapper==True):


1.0rc2 (Nov 19, 2005)


See my email to the cheetahtemplate-discuss list on Sat. Nov. 12th for more details on these changes:

  • faster list-based buffering in DummyTrans, rather than StringIO (my benchmarks showed it to be significantly faster. collections.deque wasn’t any faster than a simple list.) [TR]
  • new CompilerSettings to tweak generated code: [TR] * alwaysFilterNone: filter out None immediately, before the filter is called * useFilters: allows you to turn them off completely and default to str() * includeRawExprInFilterArgs: allows you to disable this behaviour * autoAssignDummyTransactionToSelf: off by default
  • and automatic $trans finding without having to pass it as an arg to methods based Jonathan Mark’s suggestion. If the template’s self.transaction attribute has been set, each method of the template will use it when called. [TR]
  • applied Chris Murphy’s patch to fix a bug in the #shBang directive. [TR]

1.0rc1 (Nov 2, 2005)


  • added the compiler option “useStackFrames” for optionally turning off the default lookup method which doesn’t work with psyco because it uses stack frame introspection. When useStackFrames=False, an alternative psyco friendly lookup method is used. [TR]
  • fixed treatment of None in several filters, bug reported by Daniele Varrazzo [TR]

0.9.18 (Aug 22, 2005)

  • version bump from 0.9.18rc1 [TR]

0.9.18rc1 (Aug 15, 2005)

  • applied Philippe Normand’s patch for extended cache support [TR]
  • added filter RawOrEncodedUnicode to fix a unicode issue that was discussed on the email list on Aug. 9th 2005 [TR]

0.9.17 (May 30, 2005)

  • this is just 0.9.17rc1 repackaged [TR]

0.9.17-rc1 (May 12, 2005)

This simple bug fix release resolves some issues introduced by under-the-hood changes in release 0.9.16a1.

  • removed the use of temp files for handling imports with dynamic compilation. This removes a whole slew of issues, including a temp file security issue reported on the email list by Brian Bird. [TR]
  • fixed bug with handling of the searchList with dynamic inheritance, as reported by Brian Bird. [TR]

0.9.16 (Mar 27, 2005)

  • this is just 0.9.16b1 repackaged [TR]

0.9.16b1 (Feb 28, 2005)

  • fixed attr error in Parser.eatEncoding [TR]
  • some tweaks to Compiler.py to prevent errors with dynamically compiled templates [TR]
  • added tests for the #encoding directive [TR]

0.9.16a1 (Jan 6, 2005)

  • fixed a unicode bug in Compiler.py [TR]
  • added new EncodeUnicode filter that Rene Pijlman contributed (I optimized it slightly) and made it the default filter for all templates. [TR]
  • added test cases for handling unicode with the default filter [TR]
  • fixed a caching bug related to the #include directive. Thanks to Michael Engelhart for reporting it.[TR]
  • added the new #encoding directive to handle PEP 263 http://www.python.org/doc/2.3/whatsnew/section-encodings.html [TR]
  • Tools.CGITemplate: fix bug in comment.[MO]
  • Abort with a helpful error message if user runs ‘cheetah test’ in a directory without write permission. (Kludge in CheetahWrapper.py; we should probably move the temp files under the system tmp directory.) [MO]
  • added better string type checking for args in Template.py, as suggested by Terrel Shumway [TR]
  • minor tweak to the class attribute lookup style in the Compiler.py __getattr__ methods [TR]
  • Fix printf format bug in “cheetah c –debug”, found by Terry MacDonald. [MO]
  • Disabled NameMapperDict test (in SyntaxAndOutput.py) because the namemappers still have the dict-method bug. (Reminder: don’t use placehold names like $update that match dict method names.) [MO]
  • #repeat now uses a local variable of the form __i$num which permits nesting [JJ]
  • implemented a modified version of Bob and JJ’s patch for better parser warnings about mismatched directives and #end directives [TR]
  • lots of little cleanups and refactoring [TR]
  • refactored the class tree for the Parser and Compiler. They are now completely separate trees and the communication between them is one-way: explicit commands from the parser to the compiler. The parser now handles all parsing tasks by itself and delegates *all* code generation to the compiler. This last bit was my original intention, but things got a bit mixed up over time. Also, all SettingsManager stuff for handling compiler/parser settings is now handled by ModuleCompiler. This should make it easier to grok, maintain, and extend both. [TR]
  • improved the parsing of singe-line #if directives. [TR]
  • removed the old webware example of the cheetah site, as it was way out of date and was more confusing than helpful. [TR]
  • added two new lookup functions to NameMapper (valueFromFrame and valueFromFrameOrSearchList) and synchronized the behaviour of the C and Python versions of all functions. [TR]
  • improved the exception handling of both versions of NameMapper. NotFound exceptions now include more detail about what wasn’t found. [TR]
  • made NameMapper’s searchList lookup functions work with any iterable type/class rather than just with lists. [TR]
  • added and updated a variety of test cases. [TR]
  • checked in a patch to CheetahWrapper that improves handling of the odir option when the path is absolute. I can’t remember where the patch came from. [TR]
  • checked in a patch to Template.py for better include/import support under Jython. Again, I’ve forgotten who contributed it. [TR]
  • updated various bits of the user guide. [TR]
  • made the Cheetah NameMapper calls in the generated code use the new function valueFromFrameOrSearchList rather than passing locals, searchList, globals, and __builtins__ into valueFromSearchList. This is faster, less bug prone and simpler to read/grok. I also removed all tracking of local variable names by the compiler. [TR]
  • other misc. refactorings [TR]

0.9.15 (Mar 25, 2003)

  • a minor tweak to the cleanup actions of one of the test cases [TR]

0.9.15rc2 (Mar 23, 2003)

  • Fixed a python version dependency bug related to Compiler.py’s use of isinstance() [TR]

0.9.15rc1 (Mar 21, 2003)

This is just 0.9.15b1 renamed.

0.9.15b1 (Mar 17, 2003)

  • The Cheetah version of unittest now prints a blank line after each traceback to separate them. (MO)
  • .webInput() now saves the cgi.FieldStorage() instance in a global variable rather than recreating it each call. That should allow the method to be called multiple times with POST variables outside Webware. (MO)
  • CheetahWrapper: no verbose output on stdout with –stdout/-p. (MO)
  • “#indent” is now undocumented. The existing code remains intact for now. See the TODO file for our future plans. (MO)
  • Apply 2 unicode-support patches from Rodrigo B. de Oliveira (rodrigobamboo) that affected the Template and ModuleCompiler classes. (TR)
  • Template: compiling a template from a string now works if the current directory doesn’t have write permission. (MO)
  • remove temporary .pyo files in addition to .py and .pyc files (TR)

0.9.15a3 (Nov 10, 2002)

  • corrected a dictionary bug in the Python version of NameMapper (TR)
  • Rewrote the “cheetah” command (CheetahWrapper.py) again and added test cases. New options –flat and –nobackup; –stdout is now a synonym for -p. See the “cheetah compile” section in the Users’ Guide for details. Deleted Utils.dualglob: merged into CheetahWrapper. (MO)
  • .addToSearchList() and .prependToSearchList() are gone. Instead of adding containers to the searchList after instantiation, pass all the containers you need to the constuctor, keep another reference somewhere to the containers, and modify the containers directly. Generic libraries that want to add a new kind of information to the searchList (e.g., web variables) should do “self.searchList().insert(0, myContainer)”. (MO)

0.9.15a2 (Nov 4th, 2002)

  • Filters now have access to the name of the placeholder they’re filtering. In the .filter() method, kw[‘rawExpr’] gives the entire placeholder name including subscripts and arguments, exactly as it appears in the template definition. (TR)
  • Fix three bugs in “cheetah compile -R”: (1) the generated class name contained the subdirectory, (2) the destination path did not contain the subdirectory, (3) Cheetah failed to create the destination subdirectory if missing. All subdirectories created have an “__init__.py” file. “cheetah fill -R” does the same thing but does not create “__init__.py”. (MO) NOTE: this is still buggy!
  • New directory “attic” in source contains code that has been abandoned for now but may come in handy someday. (MO)
  • Tests.CheetahWrapper: test suite for “cheetah compile” and “cheetah fill”. If the module is run from the command line, the option “–list PATH/CheetahWrapper.py”, lists all scenarios that would be tested; the argument is the path to the test module itself. (MO)
  • made Cheetah.NameMapper.NotFound subclass the builtin LookupError (TR)
  • added an initial implementation of single line #if directives #if <condition> then <true> else <false> The parsing is fairly rudimentary for now and assumes that the keywords ‘then’ and ‘else’ won’t appear any inside a string in this directive (TR)

0.9.15a1 (Oct 6th, 2002)

  • fixed a package-relative import bug in ImportHooks.py (TR)

  • set ‘monitorSrcFile’ to false as it was causing problems with the ImportHooks … This might be temporary as the problem needs more thought (TR)

  • fixed meta tag http_equiv to be http-equiv in SkeletonPage (TR)

  • $webInput (Utils.WebInputMixin) ‘source’ arg can be either case. (MO)

  • fixed code-gen bug in MethodCompiler.commitStrConst that was leading to triple single quotes followed immediately by another single quote if the template def contained a ‘$placeholder’ surrounded in single quotes and multiple \n newlines … plus added new test case.(TR)

  • undocumented the ‘#settings’ directive. The directive itself will be removed soon. (MO)

  • Utils.optik: Optik 1.3 package by Gregory P Ward, for parsing command-line options in ‘cheetah’ comamnd. Copied unchanged into Cheetah except added “Cheetah.Utils.optik.” prefix to intra-package imports. Optik’s copyright and license is in an appendix in the Cheetah Users’ Guide. (MO)

  • rewrite of the “cheetah” and “cheetah-compile” commands. The command-line options have changed! Removed CheetahCompile module removed and its test suite too; CheetahWrapper now takes its place. (MO)

  • Utils.dualglob: new module to recursively generate source+destination filenames from command-line filespecs. (MO)

  • The command-line options of .py template modules have also changed to conform with the “cheetah” command. Also a –pickle bug was fixed. (MO)

  • Utils.WebMixin: made a string type comparision backward compatible. This was why the Cheetah test suite was failing on Python < 2.2! (MO)

  • SettingsManager._createConfigFile(): bugfix in default argument. (MO)

  • $hasVar(‘varName’) is an alias for $varExists(‘varName’). (MO)

  • $_fileDirName and $_filePath are now None rather than missing if the template definition did not come from a named file. (MO)

  • applied patch on SourceForge for “%” in default arguments of a block (TR)

  • removed the _underscored attribute lookup step from NameMapper NOTE THIS MIGHT BREAK EXISTING TEMPLATES (TR)

  • Install Cheetah into site-packages/Cheetah/ rather than site-packages/Webware/Cheetah/. Added code to automatically remove the old dir.(TR)

  • fixed the variable name resolution order bug in $placeholders. The new implementation uses:

    valueFromSearchList([locals()] + searchList + [globals(), __builtin__],
    rest of the args) for all lookups. (TR)
  • removed the #settings directive (TR)

  • added the #del directive, for using Python’s del statement (TR)

  • I think I’ve fixed the problem with the searchList arg being discarded when a template is generated from a .tmpl file that #extends another template. This bug was reported by Edmund on Aug 30th (subject: “Bug? Was: Really basic searchList question”) (TR)

0.9.14 (July 14, 2002)

  • Precompiled template Templates/SkeletonPage.py added to CVS. This file is needed for Cheetah’s regression tests. (MO)
  • removed automatic recompilation of .py template in memory if the .tmpl file has changed. (TR)

0.9.14b1 (June 30, 2002)

  • moved the Users’ Guide and the Developers’ Guide into a separate CVS module, ‘CheetahDocs’, so they can be distributed separately from the source distro (TR,MO)
  • added TypeType to the types that NameMapper won’t do autocalling on (TR)
  • in Template.py moved the global LegalKWs to Template._legalKWs (TR)
  • made #set work with RVALUES that are missing the recommended $ (TR)
  • added some new test cases for the #set directive (TR)
  • fixed bug in the output of the #unless directive that Mike found (TR)
  • added some module constants to clear up a missing name bug that Mike found in cases where you use **KW in a Cheetah method definition (TR)
  • fixed a bug in Parser.py:_LowLevelSemanticsParser.getExpression() that was related to the default enclosures=[] argument. This arg was unintentionally being shared between calls and thus leading to parsing errors as reported by Greg Czajkowski (TR)
  • Filter: fixed an ‘== None’ expression (should be ‘is None’). (MO)
  • TemplateMisc: new base class for Template. This is for optional convenience methods that don’t require Webware. (MO)
  • User’s Guide: new sections “Non-Webware HTML Output” and “Non-HTML Output”. (MO)
  • Expanded $webInput() – renamed from $cgiImport() – to work both with Webware input and CGI scripts. Handles GET/POST/cookie/session vars under Webware, and GET/POST under CGI. Defined in Cheetah.Utils.WebInputMixin, now inherited by Template directly. (MO)
  • Tools.CGITemplate has methods to output CGI headers: .isCgi, .cgiHeaders and .cgiHeadersHook in TemplateMisc. (MO)
  • New #indent directive allows you to indent block constructs in the template definition without having that indentation in the output, and allows you to set the output indentation per line independent of the indentation in the template definition. This version uses Robert Kuzelj’s #indent syntax exactly. In the next few days, Cheetah.Utils.Indenter will be refactored and *** THE #INDENT SYNTAX WILL CHANGE! *** (MO)
  • added the #return directive as requested by Robert Kulezj (TR)
  • added some test cases for the #return directive (TR)
  • removed buggy import statement that had been left in Servlet.py after the CGIInputMixin changes (TR)

0.9.13 (May 8, 2002)

  • changed Cheetah.Servlet.isRunningFromWebKit to isWebwareInstalled (TR)

  • fixed parsing bug that would exit an expression if the directiveEndToken was a valid Python token and was found inside the directive. (TR)


    directiveStartToken = .
    directiveEndToken = :
    commentStartToken = #
    #end compiler-settings
    .for a in [1,2,3,4][2:3]:
    .end for
  • fixed #include bug that was resulting in non-unique includeIDs (TR)

0.9.13b2 (May 3, 2002)

  • fixed the bug in Cheetah.Servlet.Servlet.serverSidePath that Jeff Johnson found. (TR)
  • changed the attribute Cheetah.Servlet.ServletisRunningFromWebKit to isControlledByWebKit and set the default to False unless the .awake method is called. This makes a clear distinction between templates that are being used with WebKit via the inheritance approach and the containment approach (TR)

0.9.13b1 (May 1, 2002)

  • Was going to import cStringIO instead of StringIO, but it made the DummyTransaction.py unittest fail so I undid it. Cheetah aims to provide Unicode support, which cStringIO does not provide. (TR/MO)
  • Utils.Misc.CheckKeywords(): prevent misspelled keyword arguments, used by Template constructor. (MO)
  • removed support for multiple inheritance (TR)
  • added some bounds-checking code to _namemapper.c’s getNameChunks function (TR)
  • changed the exceptions in _namemapper.c from the old string exceptions to proper exception objects (TR)
  • first portion of Developers’ Guide written (MO)
  • implemented the extended #extends directive, which does automatic importing (MO,TR)
  • added some new testcases for the extended #extends directive (TR)
  • lots of work on the Users’ Guide (MO)
  • implemented and tested an import hook for .tmpl files (TR):
    import MyTemplate # will compile and import MyTemplate.tmpl
  • made my True/False declarations friendly with Python 2.2.1, which already includes True/False as builtins (TR)
  • implemented the #compiler directive that Edmund Lian suggested (TR)
    #compiler commentStartToken = ‘//’ // a comment #compiler reset // no longer a comment
  • fixed the bug that Edmund Lian found in .addSet() when useNameMapper = 0 (TR)
  • fixed bug in comment creation using lineCol that Mike found (TR)

0.9.12 (April 3, 2002)

  • no code changes from beta 2
  • more work on the docs (MO)

0.9.12b2 (Mar 28, 2002)

  • fixed Win32 path bug in Template._makeDummyPackageForDir() (TR)
  • prettied up the format of the debug comments in the Cheetah generated Python code (TR)
  • fixed the non-unique key error in Template._includeCheetahSource (TR)
  • fixed the module import bug in ‘cheetah compile -w’ (TR)

0.9.12b1 (Mar 24, 2002)

  • $request().field(args) now works, identical to $request.field(args) to implement this, the request object is now self.request() instead of self.request. This provides compatibility with Webware’s servlet API. (self.session already was an accessor method). New read-only attribute self.isRunningFromWebKit is boolean. All changes are in Servlet.py. (MO)
  • fixed nested-NotFound bug in _namemapper.c’s valueFromSearchList (TR)
  • ‘cheetah’ wrapper script has abbreviation -c for the ‘compile’ command, -t for ‘test’, and an ASCII-art cheetah face in the help message. (MO)
  • CheetahCompile.py: fixed to recognize –help option and to show –help/-h in help message. (MO)
  • CheetahCompile.py: changed the order of the VERBOSE mode printouts, as per Mike’s request (TR)
  • Template.py: fixed the #include’d template searchList sharing problem, as reported by Johannes (TR)
  • corrected namemapper translation bug in Compiler.GenUtils.genNameMapperVar() (TR)
  • Utils.Misc.UseOrRaise(): convenience function to return a value, or raise it if it’s a subclass of Exception. (MO)
  • Utils.CGIImportMixin replaces Tools.WebwareMixin. Servlet now subclasses it. This adds the .cgiImport() method to all servlets, allowing sophisticated retrieval of form fields, cookies or session variables from one line of Cheetah or Python code. See module docstring. (MO)
  • lots of updates to the docs (MO)

0.9.11 (Mar 07, 2002)

  • fixed a careless bug in cheetah-compile (TR)
  • implemented the new ‘cheetah’ wrapper script (TR)
  • refactored the local copy of unittest a bit (TR)

0.9.10 (Mar 06, 2002): Primarily a bug fix release

  • fixed bug in srcfile-mtime monitoring / update code (TR)
  • fixed the parsing of single-line #defs and #blocks so they can have arguments (TR)
  • added test cases for single-line #defs and #blocks with args (TR)
  • fixed a silly typo bug in Parser.py where a comma was left at the end of regex definition, make it a tuple rather than a regex
  • fixed the directive matching bug that Jeff Johnson reported. It was causing #else# to not match, while #else # was matching. + added a test for it.(TR)
  • fixed bug in a regex that was preventing bare $’s followed by whitespace and then valid varname chars from parsing as just $ instead of as a placeholder (TR)
  • added some code to break reference cycles after the compilation is complete. This helps prevent memory leaks when a process in creating then discarding lots of Templates. You also need to manually call “template.shutdown()” to clear the remaining reference cycles. (TR)
  • fixed string formating bug in the autogenerated docstring code (TR)
  • added better error message for the #attr directive (TR)
  • removed some residual code that was causing a bug with cheetahvars that started with the name of one of the imported modules, such as ‘time’. (TR)

0.9.9 (Dec 14, 2001)

  • implemented one-line #def’s and #block’s (TR):

    #def aTest: This is a \$adj test   ---- READ THE MANUAL FOR MORE INFO.

    NOTE: leading and trailing whitespace is stripped. These should only be used on lines by themselves as it reads to the end of the line.

  • made cheetah-compile accept input on standard input (TR)

  • made sure that #def and #block work with $’s on the method names (TR)

0.9.9b1 (Dec 6, 2001)

  • template constructor arg ‘outputFilter’ now ‘filter’, for consistency with #filter (MO)
  • template constructor raises TypeError if bad arguments (MO)
  • Cheetah.Utils.VerifyType new module containing functions for verifying the type of an argument (MO)
  • Cheetah.Utils: new package for non-Cheetah-specific modules needed by Cheetah (MO)
  • Cheetah.Filters: new filter WebSafe, several bugfixes (MO)
  • more work on the Users’ Guide (MO)
  • fixed bug with adding Python’s __builtins__ to the local vars list (TR)
  • fixed bug with #echo (TR)
  • fixed bug that was preventing ${a, $b=1234} from working like ${a, b=1234} (TR)
  • fixed some bugs in Template.varExists and Template.getVar() (TR - thanks to MH for spotting them)
  • made it possible to use filenames like ‘spam-eggs.txt’ that have invalid characters for module names with Template(): Template(file=’spam-eggs.txt’) (TR/MH)
  • refactored ‘cheetah-compile’ a little (TR)
  • Cheetah.Filters.Strip: new filter to strip leading/trailing whitespace but preserve newlines. Suitable for #filter directive or (possible) future #sed directive. (MO)
  • Cheetah.Filters.StripSqueeze: new filter to canonicalize all whitespace chunks to ‘ ‘. Also removes all newlines (joining multi-line input into one long line), and leading/trailing whitespace from the final result. (MO)
  • Filters can now be used standalone for debugging or for use outside Cheetah. This works transparently; details are in Filters.py docstring. (MO)
  • Cheetah.Tools.MondoReport: new module for dividing a long list into “pages”, and for calculating statistics useful in reports. (MO)
  • refactored Cheetah.Servlet.Servlet.Awake a little (TR)
  • fixed an output bug in the #block generated code that turned up when you tried to override a block method from Python rather than Cheetah. (TR)
  • started preparing to shift some of the ‘shared’ utility classes, such as SettingsManager, to the Webware core. Cheetah 1.0 will probably require Webware to be installed so it can access those shared classes. (TR)
  • extended the template module command line interface(TR/MO)

0.9.9a6 (Nov 6, 2001)

  • fixed bug with quotations in longer constant string chunks (TR)
  • fixed another bug in the cheetah-compile script (TR)
  • fixed a bug in the file-update monitoring code that was resulting in infinite loops when used with Template sub-classes (TR)
  • extended the #filter framework according to Mike’s suggestions (TR)
  • added test modules for cheetah-compile and the file-update monitoring code (TR)
  • extended the capabilities of cheetah-compile … (IB)
  • updated the docs (MO)

0.9.9a5 (October 31, 2001)

  • fixed a bug I created yesterday (TR)

0.9.9a4 (October 30, 2001)

  • added #repeat (TR implementing Chuck’s suggestion)
  • added #unless (TR implementing Mike’s suggestion)
  • updates to the Users’ Guide (MO)
  • fixed a small bug in the cheetah-compile script, as reported by Ian on the list (TR)

0.9.9a3 (October 12, 2001)

  • more in the Users Guide (TR)
  • renamed #attribute as #attr (TR)
  • renamed #call as #silent (TR)
  • added #echo directive (TR)

0.9.9a2 (October 11, 2001)

  • updated the example site and the SkeletonPage framework (TR)
  • fixed some small bugs (TR)
  • corrected some typos in the docs (TR + MO)
  • added Ian’s sitehiearchy class to Cheetah.Tools (TR + IB)

0.9.9a1 (October 9, 2001) [many changes and bug-fixes]

  • a complete reimplementation of Cheetah’s core (the parser and compiler classes) (TR + IB)
  • implemented the #def, #implements, #import, and #from directives + removed #redefine and #macros + renamed #extend as #extends (TR + IB)
  • replaced #data with #settings, see the docs (TR)
  • restructured and updated the docs (TR + MO + IB)
  • reimplemented the cheetah-compile script, without the -g option that Ian had added (TR)
  • changed the signature of Template.__init__. See the docs. (TR)
  • made #set distinguish between local and global vars. See the docs. (TR)
  • added hundreds of new test cases (TR)
  • added the #breakpoint and #compiler-settings directives (TR)
  • started restructuring the SkeletonPage framework [not complete yet] (TR)
  • started restructuring the example sites [not complete yet] (TR)

0.9.8 (October 9, 2001)

  • added a few new language constructs (aka ‘directives’) to Cheetah (TR) #while … #end while #try … #except … #else … #finally … #end try
  • fixed a bug in the handling of local vars in #for loops that was preventing callable local vars from being handled properly. See Chuck’s post of Sept 10. (TR)
  • fixed a pointer bug in the C version of NameMapper.valueFromSearchList() that was yielding undefined values for the NotFound exception when it was raised (TR)
  • prefaced all internal args to Template() with underscores (TR)
  • fixed the problem with parsing triple quoted strings in arg lists (TR)
  • updated the docs (TR)

0.9.8a4 (September 7, 2001)

  • Added -g (appendGen function argument), which compiles x.tmpl to xGen.py, with x.py being for non-generated Python code. Also changed option handling a little and added a comment to the top of compiled files. (IB + MO)

  • finalized the #include syntax after a lengthy discussion on the list This is different from in 0.9.8a3 (TR):

    #include <ARGS> <EXPR> … uses the value of EXPR as the path of the file to include.

    #include <ARGS> source = <EXPR> … includes the value of the EXPR

    where <ARGS> is ‘raw’ or ‘’

  • re-implemented the output mechanism to use streaming via Webware’s Transaction and Response objects when available and fake it with the DummyTransaction DummyResponse classes when the Webware Transaction is not avialable. This behaviour is roughly the same as in Webware’s PSP. Will implement output buffering PHP-style later if there is any demand. (TR)

  • made #include a run-time directive rather than compile-time. This is slower, but the semantics are better. (TR)

  • various small optimizations to the generated code (TR)

  • updated the docs (TR)

0.9.8a3 (August 22, 2001) [includes changes for 0.9.8a1 and 0.9.8a2]

  • Added package ./src/Tools/ for contributed classes/functions/packages not necessary to run Cheetah. The first such class is RecursiveNull.py by Ian Bicking. Added package Cheetah.Tools to list in ./setup.py . (MO)

  • Template.__init__ keyword arg ‘searchList’: no longer has to be a tuple. It may be a list or any type that that Python’s ‘tuple’ function accepts. (MO)

  • Template.__init__ new keyword arg ‘file’: this may be a filename or file object to read the Template Definition from. If you use this, you must not pass a Template Definition string also. New instance variables ._fileName and ._fileMtime are set if a filename was passed; otherwise they are None. (MO)

  • CodeGenerator new function ‘varNotFound_KeyError’: raises KeyError if a placeholder name is missing when filling the template. Disabled by default. (MO) NB - this change has been superceeded by ‘errorCheckers’

  • Template.getUnknowns (new method): returns a list of Placeholder Names missing in the Search List. (MO) - this change has been superceeded by ‘errorCheckers’

  • made changes to Template.py, CodeGenerator.py, PlaceholderProcessor.py, and TagProcessor.py to enable customization of the placeholderStartToken so it can be set to any character sequence, rather than just the default ‘$’. This is configurable by the Template setting ‘placeholderStartToken’ (TR)

  • fixed a small bug in PlaceholderProcessor.processTag() that prevented static caching (i.e. $*) of a value containing ‘’’ style quotes

  • added #break and #continue (TR)

  • fixed the relative path problem with #include when using Cheetah with WebKit (TR)

  • implemented the #stop directive (TR)

  • fixed a bug in the macro processing that prevented macros defined inside #includes from being visible at the top level (TR)

  • fixed a bug in the handling of the setting ‘useAutocalling’ (TR)

  • fixed some bugs in the handling of macros (TR)

  • completed the transition to nested template #includes (TR)

  • added direct #includes (TR)

  • completed the transition to run-time evaluation (TR)

  • renamed the .startServer() method of Template to .compile() (TR)

  • renamed the ‘delayedStart’ setting as ‘delayedCompile’ (TR)

  • added .redefineTemplateBlock as an alias to Template.defineTemplateBlock (TR)

  • got relative path includes working with Webware and Cheetah.Servlet (TR)

  • lots of changes in the docs (TR & MO)

  • implemented a C version of NameMapper (TR + CE)

  • added the ‘errorCheckers’ framwork (TR)

  • added the ‘formatters’ framework and the #formatter directive

  • a major restructuring of the modules and internal API (TR)

  • made sure that all the #directives with start and end tags are implemented in such a way that they won’t cause ‘maximum recursion’ limit errors if their content block is long. Simple regexes didn’t cut it in these cases. (TR)

    • #macro
    • multiline comments
    • #data
    • #block
    • #raw
    • the parsing of the core tags (the state-dependent ones) after they have been translated to the internal delimiters
  • made a Template.shutdown() method for cleaning up reference cycles before a template object is deleted. (TR)

  • made the parsing and processing of #macros() more robust (TR)

  • implemented the file update checking mechanism (TR) NOTE, the syntax for the #include is now:

    #include <ARGS> file = <EXPR>
    ... uses the value of EXPR as the path of the file to include.
    #include <ARGS> <EXPR>
    ... includes the value of the EXPR

    where <ARGS> is ‘raw’ or ‘direct’

0.9.7 (July 13, 2001)

  • reimplemented the parsing of $placeholders using the Python tokenize module (TR)
    • now translates into Python code instead of going through NameMapper for each request
    • supports arg lists and nested placeholders
    • maintained support for autocalling of functions and methods, will do this serially for $func.otherFunc, etc.
  • reimplemented the #include and #raw directives using nested templates for parsed includes and string attributes of ‘Template’ to store raw text The support for file update monitoring of includes is still not implemented (TR)
  • moved some stuff from __init__.py into CHANGES and TODO (TR)
  • added a new command ‘sdist_docs’ to setup.py which rebuilds the docs when making a source distribution (TR)
  • changed the name of the ./Cheetah dir to ./src (TR)
  • fixed a bug in one of the code filters that was preventing commas from being used between $placeholders (TR)
  • generalized the line ending regex for single-line comments (TR)
  • corrected the spelling of ‘Delimiters’ throughout Cheetah (TR)
  • made insertLines in Utilities.py more robust (Chuck)
  • added key argument to raising some NotFound exceptions in NameMapper (Chuck)
  • fixed strange bug involving missing templateObj parameter in PlaceholderProcessor.py(Chuck)
  • expanded on the docs (Mike)

0.9.6 (June 12, 2001)

  • fixed a bug in NameMapper that was preventing ‘obj.__class__.__name__’ from mapping (TR)

0.9.5 (June 10, 2001)

  • implemented the #cache directive - see the mailing list (TR)
  • reworked the handling of cached $placeholders and set $var to mean NO_CACHE, $*var to mean STATIC_CACHE, and $*15*var to mean TIMED_REFRESH_CACHE (TR)
  • renamed Template._getValueForName as Template.mapName (TR)

0.9.4 (June 9, 2001)

  • created a SettingsManager base class to handle settings for the Template class (TR)
  • moved the HTML docs icons into the same dir as the HTML (TR)


  • updated the User’s Guide Makefile. Builds HTML, PDF, and PS in the ./docs dir now. (TR)
  • changed the refs to ‘Tavis Rudd’ in the docs to ‘The Cheetah Development Team’ (TR)
  • added a few bits to the docs (TR)
  • did some internal renaming so ‘nameMapperTags’ are referred as ‘placeholderTags’ (TR)
  • added the #slurp directive (TR)


  • got the PSP plugin working again. It still need test cases. (TR)


  • Changed the name of the package to ‘Cheetah’ from TemplateServer (TR)
  • Changed the name of the Server module and its TemplateServer class to ‘Template’ (TR)
  • Changed the name of the ‘TScompile’ script to ‘cheetah-compile’ (TR)
  • updated the docs (TR)


  • changed the names and behaviour of the #parse and #include directives (TR) see the docs for more. (TR)
  • changed #verbatim to #raw (TR)
  • fixed a bug in Tests.py that caused an error on the first run. (TR)
  • more docs (TR + MO)
  • ! all tests pass with Python 2.1 and 2.0 (TR)


  • changed the #directive end tags to #end if instead of #/if and #end (TR) macro instead of #/macro (TR)
  • more work on the User’s Guide (TR)
  • fixed a bug in TScompile (TR)


  • fixed a problem with the regexs that caused $vars and #directives at the (TR) very beginning of the template string not to match in Python 2.0 (TR)
  • removed some Test cases that made invalid assumptions about the order (TR) of items in dictionaries. (TR)


  • finished half of the User’s Guide (TR)
  • fixed several small bugs (TR)
  • added the #comment directive and removed the old <# multiline comment tag #> (TR)
  • changed the explicit directive closure to /# from ;# (TR)


  • several small bug fixes (TR)
  • reimplemented the #block directive to avoid maximum recursion depth errors (TR) with large blocks. (TR)
  • created many new test cases in the regression testing suite (TR)
  • added an example site to the examples/ directory (TR)
  • started the User’s Guide (TR)


  • implemented the command-line compiler (TR)


  • implemented the regression testing suite (TR)
  • fixed a number of small bugs (TR)


  • implemented the #longMacro directive (TR)


TR - Tavis Rudd
MO - Mike Orr
JJ - Shannon 'jj' Behrens
IB - Ian Bicking
CE - Chuck Esterbrook
MH - Mike Halle