ANN: EmPy version 2.3 -- A templating system in Python

[Erik Max Francis]

Summary

    A templating system for Python.


Overview

    EmPy is a system for embedding Python expressions and statements
    in template text; it takes an EmPy source file, processes it, and
    produces output.  This is accomplished via expansions, which are
    special signals to the EmPy system and are set off by a special
    prefix (by default the at sign, '@').  EmPy can expand arbitrary
    Python expressions and statements in this way, as well as a
    variety of special forms.  Textual data not explicitly delimited
    in this way is sent unaffected to the output, allowing Python to
    be used in effect as a markup language.  Also supported are "hook"
    callbacks, recording and playback via diversions, and dynamic,
    chainable filters.  The system is highly configurable via command
    line options and embedded commands.

    Expressions are embedded in text with the '@(...)' notation;
    variations include conditional expressions with '@(...?...:...)'
    and the ability to handle thrown exceptions with '@(...$...)'.  As
    a shortcut, simple variables and expressions can be abbreviated as
    '@variable', '@object.attribute', '@function(arguments)',
    '@sequence[index]', and combinations.  Full-fledged statements
    are embedded with '@{...}'.  Forms of conditional, repeated, and
    recallable expansion are available via '@[...]'.  A '@' followed
    by a whitespace character (including a newline) expands to
    nothing, allowing string concatenations and line continuations.
    Comments are indicated with '@#' and consume the rest of the line,
    up to and including the trailing newline.  '@%' indicate
    "significators," which are special forms of variable assignment
    intended to specify per-file identification information in a
    format which is easy to parse externally.  Escape sequences
    analogous to those in C can be specified with '@\...', and finally
    a '@@' sequence expands to a single literal at sign.


Getting the software

    The current version of empy is 2.3.

    The latest version of the software is available in a tarball here:
    http://www.alcyone.com/pyos/empy/empy-latest.tar.gz.

    The official URL for this Web site is
    http://www.alcyone.com/pyos/empy/.


Requirements

    EmPy should work with any version of Python from 1.5.x onward.  It
    has been tested with all major versions of CPython from 1.5 up,
    and Jython from 2.0 up.  The included test script is intended to
    run on UNIX-like systems with a Bourne shell.


License

    This code is released under the GPL.


Mailing lists

    There are two EmPy related mailing lists available.  The first is
    a receive-only, very low volume list for important announcements
    (including releases).  To subscribe, send an email to
    mailto:empy-announce-list-subscribe at alcyone.com.

    The second is a general discussion list for topics related to
    EmPy, and is open for everyone to contribute; announcements
    related to EmPy will also be made on this list.  The author of
    EmPy (and any future developers) will also be on the list, so it
    can be used not only to discuss EmPy features with other users,
    but also to ask questions of the author(s).  To subscribe, send an
    email to mailto:empy-list-subscribe at alcyone.com.

	...

Release history [since 2.2]

    - 2.3; 2003 Feb 20.  Proper and full support for concurrent and
      recursive interpreters; protection from closing the true stdout
      file object; detect edge cases of interpreter globals or
      'sys.stdout' proxy collisions; add globals manipulation
      functions 'empy.getGlobals', 'empy.setGlobals', and
      'empy.updateGlobals' which properly preserve the 'empy'
      pseudomodule; separate usage info out into easily accessible
      lists for easier presentation; have -h option show simple usage
      and -H show extened usage; add 'NullFile' utility class.

    - 2.2.6; 2003 Jan 30.  Fix a bug in the 'Filter.detach' method
      (which would not normally be called anyway).

    - 2.2.5; 2003 Jan 9.  Strip carriage returns out of executed code
      blocks for DOS/Windows compatibility.

    - 2.2.4; 2002 Dec 23.  Abstract Filter interface to use methods
      only; add @[noop: ...] substitution for completeness and block
      commenting.

    - 2.2.3; 2002 Dec 16.  Support compatibility with Jython by
      working around a minor difference between CPython and Jython in
      string splitting.

    - 2.2.2; 2002 Dec 14.  Include better docstrings for pseudomodule
      functions; segue to a dictionary-based options system for
      interpreters; add 'empy.clearAllHooks' and 'empy.clearGlobals';
      include a short documentation section on embedding interpreters;
      fix a bug in significator regular expression.

    - 2.2.1; 2002 Nov 30.  Tweak test script to avoid writing
      unnecessary temporary file; add 'Interpreter.single' method;
      expose 'evaluate', 'execute', 'substitute', and 'single' methods
      to the pseudomodule; add (rather obvious) 'EMPY_OPTIONS'
      environment variable support; add 'empy.enableHooks' and
      'empy.disableHooks'; include optimization to transparently
      disable hooks until they are actually used.

-- 
 Erik Max Francis / max at alcyone.com / http://www.alcyone.com/max/
 __ San Jose, CA, USA / 37 20 N 121 53 W / &tSftDotIotE
/  \ It's better to be quotable than to be honest.
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