Metadata-Version: 1.0
Name: say
Version: 0.833
Summary: Super-simple templated printing. E.g.: say("Hello, {whoever}!", indent=1)
Home-page: https://bitbucket.org/jeunice/say
Author: Jonathan Eunice
Author-email: jonathan.eunice@gmail.com
License: UNKNOWN
Description: ``print``, ``format``, and ``%``, evolved.
        
            **Q:** It's been *forty years* since ``C`` introduced ``printf()`` and the basic
            formatted printing of positional parameters. Isn't it time for an upgrade?
        
            **A:** Yes! ZOMG, yes!
            
        ``say`` supplements or replaces Python's ``print``
        statement/function, ``format`` function/method, and ``%`` string interpolation
        operator with higher-level facilities:
        
         *  Straightforward string formatting with DRY, Pythonic
            templates that piggyback the built in ``format()`` method,  
            formatting syntax, and well-proven underlying engine.
         *  A single output mechanism compatible with both Python 2.x and Python 3.x.
         *  Indentation and wrapping (to help stucture output)
         *  Convenience printing functions for horizontal rules (lines), titles, and
            vertical whitespace.
        
        Usage
        =====
        
        ::
        
            from say import say, fmt, show
            
            x = 12
            nums = list(range(4))
            
            say("There are {x} things.")
            say("Nums has {len(nums)} items: {nums}")
            
        yields::
        
            There are 12 things.
            Nums has 4 items: [0, 1, 2, 3]
        
        ``say`` is basically a simpler, nicer recasting of::
            
            print "There are {} things.".format(x)
            print "Nums has {} items: {}".format(len(nums), nums)
            
        (NB in Python 2.6 one must number each of the ``{}`` placeholders--e.g. ``"Nums
        has {0} items: {1}"``-- in order to avoid a ``ValueError: zero length field name
        in format`` error. Python 2.7 and later assume the placeholders are sequential.)
            
        The more items that are being printed, and the complicated the ``format``
        invocation, the more valuable having it stated in-line becomes. Note that full
        expressions are are supported. They are evaluated in the context of the caller.
        
        Printing Where You Like
        =======================
        
        ``say()`` writes to a list of files--by default just ``sys.stdout``. But
        with it simple configuration call, it will write to different--even
        multiple--files::
        
            from say import say, stdout
            
            say.setfiles([stdout, "report.txt"])
            say(...)   # now prints to both stdout and report.txt
        
        This has the advantage of allowing you to both capture and see
        program output, without changing
        any code (other than the config statement). You can also define your own targeted ``Say`` instances::
        
            from say import say, Say, stderr
            
            err = say.clone().setfiles([stderr, 'error.txt'])
            err("Failed with error {errcode}")  # writes to stderr, error.txt
            
        Note that ``stdout`` and ``stderr`` are just convenience aliases to
        the respective 
        ``sys`` equivalents.
        
        Printing When You Like
        ======================
        
        If you want to stop printing for a while::
        
            say.set(silent=True)  # no printing until set to False
            
        Or transiently::
        
            say(...stuff..., silent=not verbose) # prints iff bool(verbose) is True
        
        Of course, you don't have to print to any file. There's a predefined sayer
        ``fmt()`` that works exactly like ``say()`` and inherits most of
        its options, but 
        doesn't print. (The
        ``C`` analogy: ``say`` **:** ``fmt`` **::** ``printf`` **:** ``sprintf``.)
        
        Indentation and Wrapping
        ========================
        
        Indentation is a common way to display data hierarchically. ``say`` will
        help you manage it. For example::
        
            say('TITLE')
            for item in items:
                say(item, indent=1)
           
        will indent the items by one indentation level (by default, each indent
        level is four spaces, but
        you can change that with the ``indent_str`` option). 
        
        If you want to change the default indentation level::
        
            say.set(indent=1)      # to an absolute level
            say.set(indent='+1')   # strings => set relative to current level
            
            ...
            
            say.set(indent=0)      # to get back to the default, no indent
        
        Or you can use a ``with`` construct::
        
            with say.settings(indent='+1'):
                say(...)
                
                # anything say() emits here will be auto-indented +1 levels
                
            # anything say() emits here, after the with, will not be indented +1
        
        And if you have a lot of data or text to print, you can easily wrap it::
        
            say("This is a really long...blah blah blah", wrap=40)
            
        Will automatically wrap the text to the given width (using Python's standard ``textwrap`` module).
        
        While it's easy enough for any ``print`` statement or function to have a few
        space characters added to its format string, it's easy to mistakenly type too
        many or too few spaces, or to forget to type them in some format strings. And if
        you're indenting strings that themselves may contain multiple lines, the simple
        ``print`` approach breaks because won't take multi-line strings into account.
        And it won't be integrated with wrapping.
        
        ``say``, however, simply handles the indent level and wrapping, and it properly
        handles the multi-line string case. Subsequent lines will be just as nicely and
        correctly indented as the first one--something not otherwise easily accomplished
        without adding gunky, complexifying string manipulation code to every place in
        your program that prints strings.
        
        This starts to illustrate the "do the right thing" philosophy behind ``say``. So
        many languages' printing and formatting functions a restricted to "outputting
        values" at a low level. They may format basic data types, but they don't provide
        straightforward ways to do neat text transformations like indentation that let
        programmers rapidly provide correct, highly-formatted ouput. Over time, ``say``
        will provide higher-level formatting options. For now: indentation and wrapping.
        
        Encodings
        =========
        
        ``say()`` and 
        ``fmt()`` try to work with Unicode strings, for example providing them as
        return values. But character encodings remain a fractious and often exasperating
        part of IT. When writing formatted strings, ``say`` handles this by encoding
        into ``utf-8``.
        
        If you are using strings containing ``utf-8`` rather than Unicode characters, ``say`` 
        may complain. But it complains in the same places the built-in ``format()`` does,
        so no harm done. (Python 3 doesn't generally allow ``utf-8`` in strings, so it's
        cleaner on this front.)
        
        You can get creative with the encoding::
        
            say('I am a truck!', encoding='base64')  # SSBhbSBhIHRydWNrIQo=
        
        Or change the default::
        
            say.set(encoding='rot-13')
            
        Knock yourself out with `all the exciting opportunites <http://docs.python.org/library/codecs.html#standard-encodings>`_!
        If you really want the formatted text returned just as it is written to files,
        use the ``encoded`` option. Set to ``True`` and it returns text in the output
        encoding. Or set to an actual encoding name, and that will be the return encoding.
        
        ``say()`` returns the formatted text with one small tweak: it removes the final
        newline if a newline is the very last character. Though odd, this is exactly
        what you need if you're going to ``print`` or
        ``say`` the resulting text without a gratuitous "extra" newline.
        
        Titles and Horizontal Rules
        ===========================
        
        ``say`` defines a few convenience formatting functions::
        
            say.title('Errors', sep='-')
            for i,e in enumerate(errors, start=1):
                say("{i:3}: {e['name'].upper()}")
                
        might yield::
        
            --------------- Errors ---------------
              1: I/O ERROR
              2: COMPUTE ERROR
        
        A similar method ``hr`` produces just a horizontal line, like
        the HTML ``<hr>`` element. For either, one can optionally 
        specify the width (``width``), character repeated to make the line (``sep``),
        and vertical separation/whitespace above and below the item (``vsep``).
        Good options for the separator might be be '-', '=', or parts of the `Unicode 
        box drawing character set <http://en.wikipedia.org/wiki/Box-drawing_character>`_.
        
        Python 3
        ========
        
        Say works virtually the same way in Python 2 and Python 3. This can simplify 
        software that should work across the versions, without all the ``from __future__
        import print_function`` hassle.
        
        ``say`` attempts to mask some of the quirky compexities of the 2-to-3 divide,
        such as string encodings and codec use. 
        
        Alternatives
        ============
        
         * `ScopeFormatter <http://pypi.python.org/pypi/ScopeFormatter>`_
           provides variable interpolation into strings. It is amazingly
           compact and elegant. Sadly, it only interpolates Python names, not full
           expressions. ``say`` has full expressions, as well as a framework for
           higher-level printing features beyond ``ScopeFormatter``'s...um...scope.
           
         * Even simpler are invocations of ``%`` or ``format()``
           using ``locals()``. E.g.::
           
               name = "Joe"
               print "Hello, %(name)!" % locals()
               # or
               print "Hello, {name}!".format(**locals())
               
           Unfortunately this has even more limitations than ``ScopeFormatter``: it only supports
           local variables, not globals or expressions. And the interpolation code seems
           gratuitous. Simpler::
           
              say("Hello, {name}!")
        
        Notes
        =====
        
         *  The ``say`` name was inspired by Perl's `say <http://perldoc.perl.org/functions/say.html>`_,
            but the similarity stops there.
            
         *  The ``show`` debug printing functions have been split into a separate package,
            `show <http://pypi.python.org/pypi/show>`_.
           
         *  Automated multi-version testing is managed with the wonderful
            `pytest <http://pypi.python.org/pypi/pytest>`_
            and `tox <http://pypi.python.org/pypi/tox>`_. ``say`` is now
            successfully packaged for, and tested against, all late-model verions of
            Python: 2.6, 2.7, 3.2, and 3.3, as well as PyPy 1.9 (based on 2.7.2).
         
         *  Debug printing via ``show()`` is now operational.
            Draft support for interactive Python and iPython. Works within imported modules,
            and at the interactive prompt, but cannot be used
            within interactively defined functions. Unknown whether that is a hard limit
            of Python introspection, or something that can be worked around over time.
        
         *  ``say`` has greater ambitions than just simple template printing. It's part
            of a larger rethinking of how output should be formatted. ``show()``
            is an initial down-payment. Stay tuned for more.
         
         *  In addition to being a practical module in its own right, ``say`` is
            testbed for `options <http://pypi.python.org/pypi/options>`_, a package
            that provides high-flexibility option, configuration, and parameter
            management.
         
         *  The author, `Jonathan Eunice <mailto:jonathan.eunice@gmail.com>`_ or
            `@jeunice on Twitter <http://twitter.com/jeunice>`_
            welcomes your comments and suggestions.
            
        To-Dos
        ======
        
         *  Provide code that allows ``pylint`` to see that variables used inside
            the ``say`` and ``fmt`` format strings are indeed thereby used.
        
        Installation
        ============
        
        ::
        
            pip install say
        
        To ``easy_install`` under a specific Python version (3.3 in this example)::
        
            python3.3 -m easy_install say
            
        (You may need to prefix these with "sudo " to authorize installation.)
Keywords: print format template interpolate say show
Platform: UNKNOWN
Classifier: Development Status :: 4 - Beta
Classifier: Operating System :: OS Independent
Classifier: License :: OSI Approved :: BSD License
Classifier: Intended Audience :: Developers
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2.6
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.2
Classifier: Programming Language :: Python :: 3.3
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Programming Language :: Python :: Implementation :: PyPy
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Classifier: Topic :: Printing
