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Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	1	<HTML>
				2	<HEAD>
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	3	<TITLE>Using Python 2.0 on the Macintosh</TITLE>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	4	</HEAD>
				5	<BODY>
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	6	<H1>Using Python 2.0 on the Macintosh</H1>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	7	<HR>
				8
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	9	This document is an introduction to using Python on the Apple
				10	Macintosh. It does not introduce the language itself, for this you
				11	should refer to the <A
				12	HREF="http://www.python.org/doc/tut/tut.html">Python Tutorial</A> by
				13	Guido van Rossum. This guide more-or-less replaces chapter two of the
				14	tutorial, and provides some additional material. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	15
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	16	The tutorial, along with other indispensible documentation like the
				17	library reference and such, is also available in a number of different
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	18	formats at <a href="http://www.python.org">
				19	www.python.org</a>. The Adobe Acrobat <code>.pdf</code>
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	20	files are probably a good choice for reading or printing the documents
				21	from your mac. <p>
				22
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	23	There is currently no good tutorial for the mac-specific features of
				24	Python, but to whet your appetite: it has interfaces to many MacOS
				25	toolboxes (quickdraw, sound, quicktime, open scripting, etc) and
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	26	various portable toolboxes are available too (Tk, complex
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	27	numbers, image manipulation, etc). Some <A HREF="index.html">
				28	annotated sample programs</A> are available to give you an idea of
				29	Python's power. <P>
				30
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	31	<h2>Using Python</h2>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	32
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	33	The best way to start using Python is by using the <code>Python IDE</code>,
				34	an integrated development environment with editor, debugger, class browser, etc.
				35	Unfortunately the IDE is not yet documented here. Fortunately, however, it does not
				36	need much documentation, so your best bet is to try it. <p>
				37
				38	<h2>Invoking the bare interpreter</h2>
				39
				40	An alternative method to use Python (and the method this document unfortunately emphasizes,
				41	see the comment above) is to use the bare interpreter and an external text editor.
				42	The name of the interpreter is <CODE>PythonInterpreter</CODE> and it is
				43	recognizable by the "16 ton" icon. You start the
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	44	interpreter in interactive mode by double-clicking its icon: <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	45
				46	<img src="html.icons/python.gif"><p>
				47
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	48	This should give you a text window with an informative version string
				49	and a prompt, something like the following:
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	50	<PRE>
Jack Jansen	cf70b84	1998-04-27 15:07:20 +0000	[diff] [blame]	51	Python 1.5.1 (#122 Aug 27, 1997) [CW PPC w/GUSI MSL]
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	52	Copyright 1991-1997 Stichting Mathematisch Centrum, Amsterdam
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	53	>>>
				54	</PRE>
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	55	The version string tells you the version of Python, whether it was
				56	built for PPC or 68K macs and possibly some options used to build the
				57	interpreter. If you find a bug or have a question about how the
				58	interpreter works it is a good idea to include the version information
				59	in your message. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	60
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	61	At the prompt you can type interactive python commands. See the
				62	tutorial for more information. The interactive window works
				63	more-or-less like a Communication Toolbox or Telnet window: you type
				64	commands at the bottom and terminate them with the <EM>[return]</EM>
				65	or <EM>[enter]</EM> key. Interpreter feedback also appears at the
				66	bottom of the window, and the contents scroll as output is added. You
				67	can use copy and paste in the normal way, but be sure to paste only at
				68	the bottom of the document.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	69
				70	<h2>Creating Python scripts</h2>
				71
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	72	The Python interpreter works in a way that is different from what you
				73	would expect of a macintosh program: the interpreter is just that: an
				74	interpreter. There is no builtin editor or other development
				75	support. Hence, to create a Python script you need an external text
				76	editor. For a first script you can use any editor that can create
				77	plain, unstyled text files, such as <CODE>SimpleText</CODE>. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	78
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	79	For more serious scripts, though, it is advisable to use a programmers
				80	editor, such as <CODE>BBEdit</CODE> or <CODE>Alpha</CODE>. BBEdit is
				81	my favorite: it comes in a commercial version but also in a
				82	fully-functional free version <CODE>BBEdit Lite</CODE>. You can
				83	download it from the <A HREF="http://www.barebones.com/">BareBones</A>
				84	site. The free version will probably provide all the functionality
				85	you will ever need. Besides the standard edit facilities it has
				86	multi-file searches and many other goodies that can be very handy when
				87	editing programs. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	88
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	89	After you have created your script in the editor of your choice you
				90	drop it on the interpreter. This will start the interpreter executing
				91	the script, again with a console window in which the output appears
				92	and in which you can type input if the script requires it. Normally
				93	the interpreter will close the window and quit as soon as the script
				94	is done executing, see below under <A HREF="#startup">startup
				95	options</A> for a way to change this. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	96
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	97	<blockquote>
				98	There is a BBEdit extension available that allows you to run Python
				99	scripts more-or-less straight from your bbedit source window. Check
				100	out the <code>Mac:Tools:BBPy</code> folder.
				101	</blockquote>
				102
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	103	It is a good idea to have the names of all your scripts end in
				104	<CODE>.py</CODE>. While this is not necessary for standalone scripts
				105	it is needed for modules, and it is probably a good idea to start the
				106	habit now. <p>
				107
				108	If you do not like to start the Python interpreter afresh for each
				109	edit-run cycle you can use the <CODE>import</CODE> statement and
				110	<CODE>reload()</CODE> function to speed things up in some cases. Here
				111	is Guido's original comment for how to do this, from the 1.1 release
				112	notes: <P>
				113
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	114	<BLOCKQUOTE>
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	115
				116	Make sure the program is a module file (filename must be a Python
				117	identifier followed by '<CODE>.py</CODE>'). You can then import it
				118	when you test it for the first time. There are now three
				119	possibilities: it contains a syntax error; it gets a runtime error
				120	(unhandled exception); or it runs OK but gives wrong results. (If it
				121	gives correct results, you are done testing and don't need to read the
				122	rest of this paragraph. :-) Note that the following is not
				123	Mac-specific -- it's just that on UNIX it's easier to restart the
				124	entire script so it's rarely useful. <P>
				125
				126	Recovery from a syntax error is easy: edit the file and import it
				127	again. <P>
				128
				129	Recovery from wrong output is almost as easy: edit the file and,
				130	instead of importing it, call the function <CODE>reload()</CODE> with
				131	the module name as argument (e.g., if your module is called
				132	<CODE>foo</CODE>, type <CODE>reload(foo)</CODE>). <P>
				133
				134	Recovery from an exception is trickier. Once the syntax is correct, a
				135	'module' entry is placed in an internal table, and following import
				136	statements will not re-read the file, even if the module's
				137	initialization terminated with an error (one reason why this is done
				138	is so that mutually recursive modules are initialized only once). You
				139	must therefore force re-reading the module with <CODE>reload()</CODE>,
				140	however, if this happens the first time you try to import the module,
				141	the import statement itself has not completed, and your workspace does
				142	not know the module name (even though the internal table of moduesl
				143	does!). The trick is to first import the module again, then reload
				144	it. For instance, <CODE>import foo; reload(foo)</CODE>. Because the
				145	module object already exists internally, the import statement does not
				146	attempt to execute the module again -- it just places it in your
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	147	workspace. </BLOCKQUOTE>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	148
				149	<h2>Clickable python scripts</h2>
				150
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	151	If you create your script with the correct creator and type, creator
				152	<CODE>'Pyth'</CODE> and type <CODE>'TEXT'</CODE>, you can double-click
				153	your script and it will automatically invoke the interpreter. If you
				154	use BBEdit you can tell it about the Python file type by adding it to
				155	the "file types" sections of the preferences. Then, if you save a file
				156	for the first time you can tell BBEdit to save the file as a Python
				157	script through the "options" choice of the save dialog. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	158
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	159	The <CODE>Scripts</CODE> folder contains a script
				160	<CODE>fixfiletypes</CODE> that will recursively traverse a folder and
				161	set the correct creator and type for all files ending in
				162	<CODE>.py</CODE>. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	163
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	164	<BLOCKQUOTE>
				165	Older releases of Python used the creator code
				166	<CODE>'PYTH'</CODE> in stead of <CODE>'Pyth'</CODE>. If you still have
				167	older Python sources on your system and named them with
				168	<CODE>'.py'</CODE> extension the <CODE>fixfiletypes</CODE> script will
				169	correct them.
				170	</BLOCKQUOTE>
				171
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	172	<h2>Interaction with the user</h2>
				173
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	174	Normally, the interpreter will check for user input (mouse clicks,
				175	keyboard input) every once in a while, so it is possible to switch to
				176	other applications while a script runs. It is also possible to
				177	interrupt the interpreter with the standard command-period keypress,
				178	this will raise the <CODE>KeyboardInterrupt</CODE> exception. Scripts
				179	may, however, turn off this behaviour to facilitate their own event
				180	handling. Such scripts can only be killed with the
				181	command-option-escape shortcut.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	182
				183	<h2><A NAME="startup">startup options</A></h2>
				184
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	185	If the <EM>option</EM> key is depressed when Python starts executing
				186	the interpreter will bring up an options dialog thru which you can
				187	influence the way the interpreter behaves. Keep the option key
				188	depressed until the dialog comes up. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	189
				190	<img src="html.icons/options.gif"><p>
				191
				192	The options modify the interpreters behaviour in the following way:
				193	<ul>
				194	<li> the interpreter goes to interactive mode (in stead of
				195	exiting) after a script has terminated normally,
				196	<li> for every module imported a line is printed telling you where the
				197	module was loaded from,
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	198	<li> do not print the values of expressions executed as statements in
				199	an interactive python (obsolete),
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	200	<li> do not buffer stdout and stderr,
				201	<li> print some debugging output during the parsing phase,
				202	<li> keep the output window open when a script terminates.
				203	</ul>
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	204	In addition, you can enter a unix-style command line which is passed
				205	to the script in <CODE>sys.argv</CODE>. Sys.argv[0] is always the name
				206	of the script being executed, additional values can be passed
				207	here. Quoting works as expected. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	208
Jack Jansen	22fa642	1996-09-05 15:15:59 +0000	[diff] [blame]	209	<BLOCKQUOTE>
				210	<EM>Warning:</EM> redirecting standard input or standard output in the
				211	command-line dialog does not work. This is due to circumstances beyond my
				212	control, hence I cannot say when this will be fixed.
				213	</BLOCKQUOTE>
				214
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	215	The default options are also settable on a system-wide basis, see the
				216	section on <A HREF="#preferences">editing preferences</A>. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	217
				218	<h2>Module search path</h2>
				219
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	220	The module search path, <CODE>sys.path</CODE>, contains the folders
				221	python will search when you import a module. The path is settable on a
				222	system-wide basis (see the preferences section), and normally
				223	comprises the current folder (where the script lives), the
				224	<CODE>Lib</CODE> folder and some of its subfolders and possibly some
				225	more. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	226
				227	<h2>Working folder</h2>
				228
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	229	The unix concept of a <I>working directory</I> does not translate
				230	directly to a similar concept on the Macintosh. To facilitate easy
				231	porting and the use of relative pathnames in scripts the interpreter
				232	simulates a working directory. When a script is started the initial
				233	working directory is the folder where the script lives. In case of an
				234	interactive interpreter the working directory is the folder where the
				235	interpreter lives. <P>
				236
				237	By the way: the "standard file" folder, the folder that is presented
				238	to the user initially for an <I>open</I> or <I>save</I> dialog, does
				239	<EM>not</EM> follow the Python working directory. Which folder is
				240	initially shown to the user is usually one of (a) the application
				241	folder, (b) the "Documents" folder or (c) the folder most recently
				242	used for such a dialog (in any Python program). This is standard MacOS
				243	behaviour, so don't blame Python for it. The exact behaviour is
				244	settable through a control panel since System 7.5.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	245
				246	<h2>Interactive startup file</h2>
				247
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	248	If the folder containing the interpreter contains a file named
				249	<CODE>PythonStartup</CODE> this file is executed when you start an
				250	interactive interpreter. In this file you could import modules you
				251	often use and other such things. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	252
				253
				254	<h2>Compiled python scripts</h2>
				255
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	256	Once a python module has been imported the interpreter creates a
				257	compiled version which is stored in a file with the ".py" extension
				258	replaced by ".pyc". These compiled files, with creator
				259	<CODE>'Pyth'</CODE> and type <CODE>'PYC '</CODE> load faster when
				260	imported (because they do not have to be parsed). The <CODE>Lib</CODE>
				261	folder contains a script <CODE>compileall.py</CODE>, running this
				262	script will cause all modules along the python search path to be
				263	precompiled, which will speed up your programs. Compiled files are
				264	also double-clickable. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	265
				266	<h2>Python resources</h2>
				267
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	268	MacPython has the ability to collect a number of compiled modules
				269	together in the resource fork of a single file. This feature is useful
				270	if you distribute a python program and want to minimize clutter: you
				271	can put all the needed modules in a single file (which could even be
				272	the interpreter itself). <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	273
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	274	If the module search path contains a filename as one of its entries
				275	(as opposed to a folder name, which is the normal case) this file will
				276	be searched for a resource with type <CODE>'PYC '</CODE> and a name
				277	matching the module being imported. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	278
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	279	The <CODE>scripts</CODE> folder contains a script
				280	<CODE>PackLibDir</CODE> which will convert a number of modules (or
				281	possibly a complete subtree full of modules) into such a resource
				282	file.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	283
				284	<h2><A NAME="preferences">Setting interpreter preferences</A></h2>
				285
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	286	The python interpreter keeps a preferences file in the standard
				287	location in the system folder. In this preferences file it remembers
				288	the default module search path and the default settings for the
				289	runtime options. The preferences are settable via
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	290	<CODE>EditPythonPrefs</CODE>. For PPC/cfm68k python this is a standalone
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	291	program living in the main Python folder, for 68K python it is a
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	292	script in the <CODE>Mac:Scripts</CODE> folder. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	293
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	294	The interface to edit the preferences is rather clunky for the current
				295	release. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	296
				297	<img src="html.icons/preferences.gif"><p>
				298
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	299	In the editable text field at the top you enter the initial module
				300	search path, using newline as a separator. There are two special
				301	values you can use here: an initial substring <CODE>$(PYTHON)</CODE>
				302	will expand to the Python home folder and a value of
				303	<CODE>$(APPLICATION)</CODE> will expand to the the python application
				304	itself. Note that the text field may extend "beyond the bottom" even
				305	though it does not have a scroll bar. Using the arrow keys works,
				306	though.<p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	307
Jack Jansen	04d5c58	1997-10-10 15:50:37 +0000	[diff] [blame]	308	The Python home folder $(PYTHON) is initially, when you install Python,
				309	set to the folder where the interpreter lives. You can change it here. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	310
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	311	Finally, you can set the default startup options here, through a
				312	sub-dialog.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	313
				314	<h2>Applets</h2>
				315
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	316	An applet is a fullblown application written in Python, similar to an
				317	AppleScript applet (and completely different from a Java
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	318	applet). Applets are currently supported on PowerPC macintoshes and on
				319	68K macintoshes if you use the CFM68K version of the interpreter,
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	320	and are created using the <CODE>BuildApplet</CODE> program. You create an
				321	applet by dropping the python source script onto BuildApplet.
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	322	<a href="example2.html">Example 2</a> is a more involved applet
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	323	with its own resource file, etc. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	324
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	325	Note that while an applet behaves as a fullblown Macintosh application
				326	it is not self-sufficient, so distributing it to a machine without an
				327	installed Python interpreter will not work: it needs the shared python
				328	execution engine <CODE>PythonCore</CODE>, and probably various modules
Jack Jansen	e272303	1996-10-22 15:29:15 +0000	[diff] [blame]	329	from the Lib and PlugIns folders. Distributing it to a machine that does
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	330	have a Python system will work. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	331
				332	<h2>Customizing applets</h2>
				333
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	334	Applets can have their own settings for the startup options and module
				335	search path. Dropping an applet on the <CODE>EditPythonPrefs</CODE>
				336	application allows you to set these, in the same way as
				337	double-clicking EditPythonPrefs allows you to set the system-wide
				338	defaults. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	339
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	340	Actually, not only applets but also the interpreter itself can have
				341	non-default settings for path and options. If you make a copy of the
				342	interpreter and drop this copy onto EditPythonPrefs you will have an
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	343	interpreter that has a different set of default settings. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	344
				345	<h2>Where to go from here</h2>
				346
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	347	The previously mentioned <A
				348	HREF="http://www.python.org/doc/tut/tut.html">Python Tutorial</A> is
				349	an excellent place to start reading if you have never used Python
				350	before. Other documentation such as the library reference manual is
				351	indexed at the <A HREF="http://www.python.org/doc/">Python
				352	Documentation</A> page. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	353
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	354	There are some <A HREF="index.html">annotated sample programs</A>
				355	available that show some mac-specific issues, like use of various
				356	toolboxes and creation of Python applets. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	357
Jack Jansen	cf70b84	1998-04-27 15:07:20 +0000	[diff] [blame]	358	The <CODE>Demo</CODE> and <CODE>Mac:Demo</CODE>
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	359	folders in the Macintosh distribution
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	360	contains a number of other example programs. Most of these are only
				361	very lightly documented, but they may help you to understand some
				362	aspects of using Python. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	363
Jack Jansen	cf70b84	1998-04-27 15:07:20 +0000	[diff] [blame]	364	Finally, there is a <code>Mac:Contrib</code> folder that contains
				365	a few contributions to Python that I couldn't fit in the normal tree
				366	but did want to distribute (many other contributions are contained
				367	throughout the distribution, but you don't see them, really).
				368
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	369	The best way to contact fellow Macintosh Python programmers is to join
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	370	the MacPython Special Interest Group mailing list. Send a message with
				371	"info" in the body to <A
				372	HREF="mailto:pythonmac-sig-request@python.org">pythonmac-sig-request@python.org</A>
				373	or view the <A
				374	HREF="http://www.python.org/sigs/pythonmac-sig/">Pythonmac SIG
				375	page</A> on the <A HREF="http://www.python.org">www.python.org</A> WWW
				376	server. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	377
				378	<h2>Troubleshooting</h2>
				379
Jack Jansen	e272303	1996-10-22 15:29:15 +0000	[diff] [blame]	380	A rather baffling error message can be "PythonCore not found" when you
				381	start the interpreter and you are sure that PythonCore is available. The
				382	message should actually say "Not enough memory in the system heap to
				383	load PythonCore".
				384	Blame Apple for the confusing message. <p>
				385
Jack Jansen	04d5c58	1997-10-10 15:50:37 +0000	[diff] [blame]	386	There appear to be problems with QuickTime for the CFM68K version of the
				387	interpreter. If you experience these please contact the SIG: some people
				388	use quicktime without problems and some not, and we are still hunting for
				389	the cause. <p>
				390
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	391	Python is a rather safe language, and hence it should be difficult to
				392	crash the interpreter of the system with a Python script. There is an
				393	exception to this rule, though: the modules that interface to the
				394	system toolboxes (windowing, quickdraw, etc) do very little error
				395	checking and therefore a misbehaving program using these modules may
				396	indeed crash the system. Such programs are unfortunately rather
				397	difficult to debug, since the crash does not generate the standard
				398	Python stack trace, obviously, and since debugging print statements
				399	will often interfere with the operation of the program. There is
				400	little to do about this currently. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	401
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	402	Probably the most common cause of problems with modules ported from
				403	other systems is the Mac end-of-line convention. Where unix uses
Jack Jansen	d9585c9	1996-05-07 15:28:20 +0000	[diff] [blame]	404	linefeed, 0x0a, to separate lines the mac uses carriage return,
				405	0x0d. To complicate matters more a lot of mac programming editors like
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	406	BBEdit and emacs will work happily with both conventions, so the file
				407	will appear to be correct in the editor but cause strange errors when
				408	imported. BBEdit has a popup menu which allows you to inspect (and
				409	set) the end-of-line convention used in a file. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	410
Jack Jansen	e272303	1996-10-22 15:29:15 +0000	[diff] [blame]	411	Python attempts to keep its preferences file up-to-date even when you
				412	move the Python folder around, etc. If this fails the effect will be
				413	that Python cannot start or, worse, that it does work but it cannot find
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	414	any standard modules. In this case, start Python and examine <code>sys.path</code>.
Jack Jansen	0fb1d82	1996-11-20 15:13:24 +0000	[diff] [blame]	415	If it is incorrect remove any Python preferences file from the system
Jack Jansen	e272303	1996-10-22 15:29:15 +0000	[diff] [blame]	416	folder and start the interpreter <em>while the interpreter sits in the main
Jack Jansen	3412c5d	1997-08-27 14:08:22 +0000	[diff] [blame]	417	Python folder</em>. This will regenerate the preferences file. You may also
				418	have to run the ConfigurePython applet again. <p>
Jack Jansen	e272303	1996-10-22 15:29:15 +0000	[diff] [blame]	419
Jack Jansen	cf70b84	1998-04-27 15:07:20 +0000	[diff] [blame]	420	<h2>Your five minutes are up. Next!</h2>
Jack Jansen	024a387	1996-07-18 16:07:05 +0000	[diff] [blame]	421
				422	The next section to check out is the <a href="index.html">annotated sample programs</a>.<p>
				423
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	424	<HR>
				425	<A HREF="http://www.cwi.nl/~jack">Jack Jansen</A>,
Jack Jansen	8a6cdcc	2000-09-10 12:02:28 +0000	[diff] [blame]	426	<A HREF="mailto:jack@cwi.nl">jack@cwi.nl</A>, 10-Sep-00.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	427
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