Demo fixes, see changelog

IPython/demo.py

@@ -1,4 +1,6 b''
 """Module for interactive demos using IPython.
+
+Sorry, but this uses Python 2.3 features, so it won't work in 2.2 environments.
 """
 #*****************************************************************************
 #       Copyright (C) 2005 Fernando Perez. <[e-mail]>
@@ -9,6 +11,7 b''
 #*****************************************************************************
 
 import exceptions
+import re
 
 from IPython.PyColorize import Parser
 from IPython.genutils import marquee
@@ -16,10 +19,16 b' from IPython.genutils import marquee'
 class DemoError(exceptions.Exception): pass
 
 class Demo:
-    def __init__(self,fname,pause_mark='# pause',auto=False):
+    def __init__(self,fname,mark_pause='# pause',mark_silent='# silent',
+                 auto=False):
+        """The marks are turned into regexps which match them as standalone in
+        a line, with all leading/trailing whitespace ignored."""
 
         self.fname = fname
-        self.pause_mark = pause_mark
+        self.mark_pause = mark_pause
+        self.re_pause = re.compile(r'^\s*%s\s*$' % mark_pause,re.MULTILINE)
+        self.mark_silent = mark_silent
+        self.re_silent = re.compile(r'^\s*%s\s*$' % mark_silent,re.MULTILINE)
         self.auto = auto
 
         # get a few things from ipython.  While it's a bit ugly design-wise,
@@ -34,7 +43,8 b' class Demo:'
         fobj = file(fname,'r')
         self.src = fobj.read()
         fobj.close()
-        self.src_blocks = [b.strip() for b in self.src.split(pause_mark) if b]
+        self.src_blocks = [b.strip() for b in self.re_pause.split(self.src) if b]
+        self.silent = [bool(self.re_silent.findall(b)) for b in self.src_blocks]
         self.nblocks = len(self.src_blocks)
 
         # try to colorize blocks
@@ -47,26 +57,32 b' class Demo:'
         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 again(self):
+        """Repeat the last block"""
         self.block_index -= 1
         self()
 
-
     def _validate_index(self,index):
         if index<0 or index>=self.nblocks:
             raise ValueError('invalid block index %s' % index)
 
     def seek(self,index):
+        """Move the current seek pointer to the given block"""
         self._validate_index(index)
         self.block_index = index-1
         self.finished = False
 
-    def show(self,index=None):
+    def show_block(self,index=None):
+        """Show a single block on screen"""
         if index is None:
+            if self.finished:
+                print 'Demo finished.  Use reset() if you want to rerun it.'
+                return
             index = self.block_index
         else:
             self._validate_index(index)
@@ -74,6 +90,21 b' class Demo:'
                       (self.fname,index,index+1,self.nblocks))
         print self.src_blocks_colored[index],
         
+    def show(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/%s)' %
+                              (fname,index,index+1,nblocks))
+            else:
+                print marquee('<%s> block # %s (%s/%s)' %
+                              (fname,index,index+1,nblocks))
+            print block,
+            
     def __call__(self,index=None):
         """run a block of the demo.
 
@@ -92,7 +123,11 b' class Demo:'
         try:
             next_block = self.src_blocks[index]
             self.block_index += 1
-            self.show(index)
+            if self.silent[index]:
+                print marquee('Executing silent block # %s (%s/%s)' %
+                              (index,index+1,self.nblocks))
+            else:
+                self.show_block(index)
             if not self.auto:
                 print marquee('Press <q> to quit, <Enter> to execute...'),
                 ans = raw_input().strip()
@@ -112,4 +147,3 b' class Demo:'
             print marquee(' END OF DEMO ')
             print marquee('Use reset() if you want to rerun it.')
             self.finished = True
-

doc/ChangeLog

@@ -1,5 +1,8 b''
 2005-09-22  Fernando Perez  <[e-mail]>
 
+	* IPython/demo.py (Demo.__init__): added support for silent
+	blocks, improved marks as regexps, docstrings written.
+
 	* IPython/genutils.py (marquee): little utility used by the demo
 	code, handy in general.