|
|
"""Module for interactive demos using IPython.
|
|
|
|
|
|
This module implements a few classes for running Python scripts interactively
|
|
|
in IPython for demonstrations. With very simple markup (a few tags in
|
|
|
comments), you can control points where the script stops executing and returns
|
|
|
control to IPython.
|
|
|
|
|
|
The classes are (see their docstrings for further details):
|
|
|
|
|
|
- Demo: pure python demos
|
|
|
|
|
|
- IPythonDemo: demos with input to be processed by IPython as if it had been
|
|
|
typed interactively (so magics work, as well as any other special syntax you
|
|
|
may have added via input prefilters).
|
|
|
|
|
|
- LineDemo: single-line version of the Demo class. These demos are executed
|
|
|
one line at a time, and require no markup.
|
|
|
|
|
|
- IPythonLineDemo: IPython version of the LineDemo class (the demo is
|
|
|
executed a line at a time, but processed via IPython).
|
|
|
|
|
|
|
|
|
The file is run in its own empty namespace (though you can pass it a string of
|
|
|
arguments as if in a command line environment, and it will see those as
|
|
|
sys.argv). But at each stop, the global IPython namespace is updated with the
|
|
|
current internal demo namespace, so you can work interactively with the data
|
|
|
accumulated so far.
|
|
|
|
|
|
By default, each block of code is printed (with syntax highlighting) before
|
|
|
executing it and you have to confirm execution. This is intended to show the
|
|
|
code to an audience first so you can discuss it, and only proceed with
|
|
|
execution once you agree. There are a few tags which allow you to modify this
|
|
|
behavior.
|
|
|
|
|
|
The supported tags are:
|
|
|
|
|
|
# <demo> --- stop ---
|
|
|
|
|
|
Defines block boundaries, the points where IPython stops execution of the
|
|
|
file and returns to the interactive prompt.
|
|
|
|
|
|
# <demo> silent
|
|
|
|
|
|
Make a block execute silently (and hence automatically). Typically used in
|
|
|
cases where you have some boilerplate or initialization code which you need
|
|
|
executed but do not want to be seen in the demo.
|
|
|
|
|
|
# <demo> auto
|
|
|
|
|
|
Make a block execute automatically, but still being printed. Useful for
|
|
|
simple code which does not warrant discussion, since it avoids the extra
|
|
|
manual confirmation.
|
|
|
|
|
|
# <demo> auto_all
|
|
|
|
|
|
This tag can _only_ be in the first block, and if given it overrides the
|
|
|
individual auto tags to make the whole demo fully automatic (no block asks
|
|
|
for confirmation). It can also be given at creation time (or the attribute
|
|
|
set later) to override what's in the file.
|
|
|
|
|
|
While _any_ python file can be run as a Demo instance, if there are no stop
|
|
|
tags the whole file will run in a single block (no different that calling
|
|
|
first %pycat and then %run). The minimal markup to make this useful is to
|
|
|
place a set of stop tags; the other tags are only there to let you fine-tune
|
|
|
the execution.
|
|
|
|
|
|
This is probably best explained with the simple example file below. You can
|
|
|
copy this into a file named ex_demo.py, and try running it via:
|
|
|
|
|
|
from IPython.demo import Demo
|
|
|
d = Demo('ex_demo.py')
|
|
|
d() <--- Call the d object (omit the parens if you have autocall set to 2).
|
|
|
|
|
|
Each time you call the demo object, it runs the next block. The demo object
|
|
|
has a few useful methods for navigation, like again(), edit(), jump(), seek()
|
|
|
and back(). It can be reset for a new run via reset() or reloaded from disk
|
|
|
(in case you've edited the source) via reload(). See their docstrings below.
|
|
|
|
|
|
#################### EXAMPLE DEMO <ex_demo.py> ###############################
|
|
|
'''A simple interactive demo to illustrate the use of IPython's Demo class.'''
|
|
|
|
|
|
print 'Hello, welcome to an interactive IPython demo.'
|
|
|
|
|
|
# The mark below defines a block boundary, which is a point where IPython will
|
|
|
# stop execution and return to the interactive prompt.
|
|
|
# Note that in actual interactive execution,
|
|
|
# <demo> --- stop ---
|
|
|
|
|
|
x = 1
|
|
|
y = 2
|
|
|
|
|
|
# <demo> --- stop ---
|
|
|
|
|
|
# the mark below makes this block as silent
|
|
|
# <demo> silent
|
|
|
|
|
|
print 'This is a silent block, which gets executed but not printed.'
|
|
|
|
|
|
# <demo> --- stop ---
|
|
|
# <demo> auto
|
|
|
print 'This is an automatic block.'
|
|
|
print 'It is executed without asking for confirmation, but printed.'
|
|
|
z = x+y
|
|
|
|
|
|
print 'z=',x
|
|
|
|
|
|
# <demo> --- stop ---
|
|
|
# This is just another normal block.
|
|
|
print 'z is now:', z
|
|
|
|
|
|
print 'bye!'
|
|
|
################### END EXAMPLE DEMO <ex_demo.py> ############################
|
|
|
"""
|
|
|
#*****************************************************************************
|
|
|
# Copyright (C) 2005-2006 Fernando Perez. <Fernando.Perez@colorado.edu>
|
|
|
#
|
|
|
# Distributed under the terms of the BSD License. The full license is in
|
|
|
# the file COPYING, distributed as part of this software.
|
|
|
#
|
|
|
#*****************************************************************************
|
|
|
|
|
|
import exceptions
|
|
|
import os
|
|
|
import re
|
|
|
import sys
|
|
|
|
|
|
from IPython.PyColorize import Parser
|
|
|
from IPython.genutils import marquee, shlex_split, file_read, file_readlines
|
|
|
|
|
|
__all__ = ['Demo','IPythonDemo','LineDemo','IPythonLineDemo','DemoError']
|
|
|
|
|
|
class DemoError(exceptions.Exception): pass
|
|
|
|
|
|
def re_mark(mark):
|
|
|
return re.compile(r'^\s*#\s+<demo>\s+%s\s*$' % mark,re.MULTILINE)
|
|
|
|
|
|
class Demo:
|
|
|
|
|
|
re_stop = re_mark('---\s?stop\s?---')
|
|
|
re_silent = re_mark('silent')
|
|
|
re_auto = re_mark('auto')
|
|
|
re_auto_all = re_mark('auto_all')
|
|
|
|
|
|
def __init__(self,fname,arg_str='',auto_all=None):
|
|
|
"""Make a new demo object. To run the demo, simply call the object.
|
|
|
|
|
|
See the module docstring for full details and an example (you can use
|
|
|
IPython.Demo? in IPython to see it).
|
|
|
|
|
|
Inputs:
|
|
|
|
|
|
- fname = filename.
|
|
|
|
|
|
Optional inputs:
|
|
|
|
|
|
- arg_str(''): a string of arguments, internally converted to a list
|
|
|
just like sys.argv, so the demo script can see a similar
|
|
|
environment.
|
|
|
|
|
|
- auto_all(None): global flag to run all blocks automatically without
|
|
|
confirmation. This attribute overrides the block-level tags and
|
|
|
applies to the whole demo. It is an attribute of the object, and
|
|
|
can be changed at runtime simply by reassigning it to a boolean
|
|
|
value.
|
|
|
"""
|
|
|
|
|
|
self.fname = fname
|
|
|
self.sys_argv = [fname] + shlex_split(arg_str)
|
|
|
self.auto_all = auto_all
|
|
|
|
|
|
# get a few things from ipython. While it's a bit ugly design-wise,
|
|
|
# it ensures that things like color scheme and the like are always in
|
|
|
# sync with the ipython mode being used. This class is only meant to
|
|
|
# be used inside ipython anyways, so it's OK.
|
|
|
self.ip_ns = __IPYTHON__.user_ns
|
|
|
self.ip_colorize = __IPYTHON__.pycolorize
|
|
|
self.ip_showtb = __IPYTHON__.showtraceback
|
|
|
self.ip_runlines = __IPYTHON__.runlines
|
|
|
self.shell = __IPYTHON__
|
|
|
|
|
|
# load user data and initialize data structures
|
|
|
self.reload()
|
|
|
|
|
|
def reload(self):
|
|
|
"""Reload source from disk and initialize state."""
|
|
|
# read data and parse into blocks
|
|
|
self.src = file_read(self.fname)
|
|
|
src_b = [b.strip() for b in self.re_stop.split(self.src) if b]
|
|
|
self._silent = [bool(self.re_silent.findall(b)) for b in src_b]
|
|
|
self._auto = [bool(self.re_auto.findall(b)) for b in src_b]
|
|
|
|
|
|
# if auto_all is not given (def. None), we read it from the file
|
|
|
if self.auto_all is None:
|
|
|
self.auto_all = bool(self.re_auto_all.findall(src_b[0]))
|
|
|
else:
|
|
|
self.auto_all = bool(self.auto_all)
|
|
|
|
|
|
# Clean the sources from all markup so it doesn't get displayed when
|
|
|
# running the demo
|
|
|
src_blocks = []
|
|
|
auto_strip = lambda s: self.re_auto.sub('',s)
|
|
|
for i,b in enumerate(src_b):
|
|
|
if self._auto[i]:
|
|
|
src_blocks.append(auto_strip(b))
|
|
|
else:
|
|
|
src_blocks.append(b)
|
|
|
# remove the auto_all marker
|
|
|
src_blocks[0] = self.re_auto_all.sub('',src_blocks[0])
|
|
|
|
|
|
self.nblocks = len(src_blocks)
|
|
|
self.src_blocks = src_blocks
|
|
|
|
|
|
# also build syntax-highlighted source
|
|
|
self.src_blocks_colored = map(self.ip_colorize,self.src_blocks)
|
|
|
|
|
|
# ensure clean namespace and seek offset
|
|
|
self.reset()
|
|
|
|
|
|
def reset(self):
|
|
|
"""Reset the namespace and seek pointer to restart the demo"""
|
|
|
self.user_ns = {}
|
|
|
self.finished = False
|
|
|
self.block_index = 0
|
|
|
|
|
|
def _validate_index(self,index):
|
|
|
if index<0 or index>=self.nblocks:
|
|
|
raise ValueError('invalid block index %s' % index)
|
|
|
|
|
|
def _get_index(self,index):
|
|
|
"""Get the current block index, validating and checking status.
|
|
|
|
|
|
Returns None if the demo is finished"""
|
|
|
|
|
|
if index is None:
|
|
|
if self.finished:
|
|
|
print 'Demo finished. Use reset() if you want to rerun it.'
|
|
|
return None
|
|
|
index = self.block_index
|
|
|
else:
|
|
|
self._validate_index(index)
|
|
|
return index
|
|
|
|
|
|
def seek(self,index):
|
|
|
"""Move the current seek pointer to the given block"""
|
|
|
self._validate_index(index)
|
|
|
self.block_index = index
|
|
|
self.finished = False
|
|
|
|
|
|
def back(self,num=1):
|
|
|
"""Move the seek pointer back num blocks (default is 1)."""
|
|
|
self.seek(self.block_index-num)
|
|
|
|
|
|
def jump(self,num):
|
|
|
"""Jump a given number of blocks relative to the current one."""
|
|
|
self.seek(self.block_index+num)
|
|
|
|
|
|
def again(self):
|
|
|
"""Move the seek pointer back one block and re-execute."""
|
|
|
self.back(1)
|
|
|
self()
|
|
|
|
|
|
def edit(self,index=None):
|
|
|
"""Edit a block.
|
|
|
|
|
|
If no number is given, use the last block executed.
|
|
|
|
|
|
This edits the in-memory copy of the demo, it does NOT modify the
|
|
|
original source file. If you want to do that, simply open the file in
|
|
|
an editor and use reload() when you make changes to the file. This
|
|
|
method is meant to let you change a block during a demonstration for
|
|
|
explanatory purposes, without damaging your original script."""
|
|
|
|
|
|
index = self._get_index(index)
|
|
|
if index is None:
|
|
|
return
|
|
|
# decrease the index by one (unless we're at the very beginning), so
|
|
|
# that the default demo.edit() call opens up the sblock we've last run
|
|
|
if index>0:
|
|
|
index -= 1
|
|
|
|
|
|
filename = self.shell.mktempfile(self.src_blocks[index])
|
|
|
self.shell.hooks.editor(filename,1)
|
|
|
new_block = file_read(filename)
|
|
|
# update the source and colored block
|
|
|
self.src_blocks[index] = new_block
|
|
|
self.src_blocks_colored[index] = self.ip_colorize(new_block)
|
|
|
self.block_index = index
|
|
|
# call to run with the newly edited index
|
|
|
self()
|
|
|
|
|
|
def show(self,index=None):
|
|
|
"""Show a single block on screen"""
|
|
|
|
|
|
index = self._get_index(index)
|
|
|
if index is None:
|
|
|
return
|
|
|
|
|
|
print marquee('<%s> block # %s (%s remaining)' %
|
|
|
(self.fname,index,self.nblocks-index-1))
|
|
|
print self.src_blocks_colored[index],
|
|
|
sys.stdout.flush()
|
|
|
|
|
|
def show_all(self):
|
|
|
"""Show entire demo on screen, block by block"""
|
|
|
|
|
|
fname = self.fname
|
|
|
nblocks = self.nblocks
|
|
|
silent = self._silent
|
|
|
for index,block in enumerate(self.src_blocks_colored):
|
|
|
if silent[index]:
|
|
|
print marquee('<%s> SILENT block # %s (%s remaining)' %
|
|
|
(fname,index,nblocks-index-1))
|
|
|
else:
|
|
|
print marquee('<%s> block # %s (%s remaining)' %
|
|
|
(fname,index,nblocks-index-1))
|
|
|
print block,
|
|
|
sys.stdout.flush()
|
|
|
|
|
|
def runlines(self,source):
|
|
|
"""Execute a string with one or more lines of code"""
|
|
|
|
|
|
exec source in self.user_ns
|
|
|
|
|
|
def __call__(self,index=None):
|
|
|
"""run a block of the demo.
|
|
|
|
|
|
If index is given, it should be an integer >=1 and <= nblocks. This
|
|
|
means that the calling convention is one off from typical Python
|
|
|
lists. The reason for the inconsistency is that the demo always
|
|
|
prints 'Block n/N, and N is the total, so it would be very odd to use
|
|
|
zero-indexing here."""
|
|
|
|
|
|
index = self._get_index(index)
|
|
|
if index is None:
|
|
|
return
|
|
|
try:
|
|
|
next_block = self.src_blocks[index]
|
|
|
self.block_index += 1
|
|
|
if self._silent[index]:
|
|
|
print marquee('Executing silent block # %s (%s remaining)' %
|
|
|
(index,self.nblocks-index-1))
|
|
|
else:
|
|
|
self.show(index)
|
|
|
if self.auto_all or self._auto[index]:
|
|
|
print marquee('output')
|
|
|
else:
|
|
|
print marquee('Press <q> to quit, <Enter> to execute...'),
|
|
|
ans = raw_input().strip()
|
|
|
if ans:
|
|
|
print marquee('Block NOT executed')
|
|
|
return
|
|
|
try:
|
|
|
save_argv = sys.argv
|
|
|
sys.argv = self.sys_argv
|
|
|
self.runlines(next_block)
|
|
|
finally:
|
|
|
sys.argv = save_argv
|
|
|
|
|
|
except:
|
|
|
self.ip_showtb(filename=self.fname)
|
|
|
else:
|
|
|
self.ip_ns.update(self.user_ns)
|
|
|
|
|
|
if self.block_index == self.nblocks:
|
|
|
print
|
|
|
print marquee(' END OF DEMO ')
|
|
|
print marquee('Use reset() if you want to rerun it.')
|
|
|
self.finished = True
|
|
|
|
|
|
class IPythonDemo(Demo):
|
|
|
"""Class for interactive demos with IPython's input processing applied.
|
|
|
|
|
|
This subclasses Demo, but instead of executing each block by the Python
|
|
|
interpreter (via exec), it actually calls IPython on it, so that any input
|
|
|
filters which may be in place are applied to the input block.
|
|
|
|
|
|
If you have an interactive environment which exposes special input
|
|
|
processing, you can use this class instead to write demo scripts which
|
|
|
operate exactly as if you had typed them interactively. The default Demo
|
|
|
class requires the input to be valid, pure Python code.
|
|
|
"""
|
|
|
|
|
|
def runlines(self,source):
|
|
|
"""Execute a string with one or more lines of code"""
|
|
|
|
|
|
self.runlines(source)
|
|
|
|
|
|
class LineDemo(Demo):
|
|
|
"""Demo where each line is executed as a separate block.
|
|
|
|
|
|
The input script should be valid Python code.
|
|
|
|
|
|
This class doesn't require any markup at all, and it's meant for simple
|
|
|
scripts (with no nesting or any kind of indentation) which consist of
|
|
|
multiple lines of input to be executed, one at a time, as if they had been
|
|
|
typed in the interactive prompt."""
|
|
|
|
|
|
def reload(self):
|
|
|
"""Reload source from disk and initialize state."""
|
|
|
# read data and parse into blocks
|
|
|
src_b = [l for l in file_readlines(self.fname) if l.strip()]
|
|
|
nblocks = len(src_b)
|
|
|
self.src = os.linesep.join(file_readlines(self.fname))
|
|
|
self._silent = [False]*nblocks
|
|
|
self._auto = [True]*nblocks
|
|
|
self.auto_all = True
|
|
|
self.nblocks = nblocks
|
|
|
self.src_blocks = src_b
|
|
|
|
|
|
# also build syntax-highlighted source
|
|
|
self.src_blocks_colored = map(self.ip_colorize,self.src_blocks)
|
|
|
|
|
|
# ensure clean namespace and seek offset
|
|
|
self.reset()
|
|
|
|
|
|
class IPythonLineDemo(IPythonDemo,LineDemo):
|
|
|
"""Variant of the LineDemo class whose input is processed by IPython."""
|
|
|
pass
|
|
|
|
