made link_str a class-level attribute based on suggestion from @takluyver

IPython/lib/display.py

@@ -1,145 +1,146 b''
 """Various display related classes.
 
 Authors : MinRK, gregcaporaso
 """
 
 from os import walk
 from os.path import join, exists, isfile, splitext
 
 
 class YouTubeVideo(object):
     """Class for embedding a YouTube Video in an IPython session, based on its video id.
 
     e.g. to embed the video on this page:
 
     http://www.youtube.com/watch?v=foo
 
     you would do:
 
     vid = YouTubeVideo("foo")
     display(vid)
     """
 
     def __init__(self, id, width=400, height=300):
         self.id = id
         self.width = width
         self.height = height
 
     def _repr_html_(self):
         """return YouTube embed iframe for this video id"""
         return """
             <iframe
                 width="%i"
                 height="%i"
                 src="http://www.youtube.com/embed/%s"
                 frameborder="0"
                 allowfullscreen
             ></iframe>
         """%(self.width, self.height, self.id)
 
 class FileLink(object):
     """Class for embedding a local file link in an IPython session, based on path
 
     e.g. to embed a link that was generated in the IPython notebook as my/data.txt
 
     you would do:
 
     local_file = FileLink("my/data.txt")
     display(local_file)
     
     or in the HTML notebook, just
     
     FileLink("my/data.txt")
     """
     
+    link_str = "<a href='%s' target='_blank'>%s</a>"
+    
     def __init__(self,
                  path,
                  url_prefix='files',
                  _result_html_prefix='',
                  _result_html_suffix='<br>'):
         """
             path : path to the file or directory that should be formatted
             directory_prefix : prefix to be prepended to all files to form a
              working link [default: 'files']
             result_html_prefix : text to append to beginning to link
              [default: none]
             result_html_suffix : text to append at the end of link
              [default: '<br>']
         """
         self.path = path
         self.url_prefix = url_prefix
-        self._link_str = "<a href='%s' target='_blank'>%s</a>"
         self._result_html_prefix = _result_html_prefix
         self._result_html_suffix = _result_html_suffix
     
     def _format_path(self):
         fp = join(self.url_prefix,self.path)
         return ''.join([self._result_html_prefix,
-                        self._link_str % (fp, self.path),
+                        self.link_str % (fp, self.path),
                         self._result_html_suffix])
         
     def _repr_html_(self):
         """return link to local file
         """
         if not exists(self.path):
             return ("Path (<tt>%s</tt>) doesn't exist. " 
                     "It may still be in the process of "
                     "being generated, or you may have the "
                     "incorrect path." % self.path)
         
         return self._format_path()
 
 # Create an alias for formatting a single directory name as a link.
 # Right now this is the same as a formatting for a single file, but 
 # we'll encorage users to reference these with a different class in
 # case we want to change this in the future.
 DirectoryLink = FileLink
 
 class FileLinks(FileLink):
     """Class for embedding local file links in an IPython session, based on path
 
     e.g. to embed links to files that were generated in the IPython notebook under my/data
 
     you would do:
 
     local_files = FileLinks("my/data")
     display(local_files)
     
     or in the HTML notebook, just
     
     FileLinks("my/data")
     
     """
     def __init__(self,
                  path,
                  url_prefix='files',
                  _included_suffixes=None,
                  _result_html_prefix='',
                  _result_html_suffix='<br>'):
         """
             included_suffixes : list of filename suffixes to include when
              formatting output [default: include all files]
              
             See the FileLink (baseclass of LocalDirectory) docstring for 
              information on additional parameters.
         """
         self._included_suffixes = _included_suffixes
         FileLink.__init__(self,
                            path,
                            url_prefix,
                            _result_html_prefix,
                            _result_html_suffix)
     
     def _format_path(self):
         result_entries = []
         for root, dirs, files in walk(self.path):
             for fn in files:
                 fp = join(self.url_prefix,root,fn)
                 # if all files are being included, or fp has a suffix
                 # that is in included_suffix, create a link to fp
                 if self._included_suffixes == None or \
                    splitext(fn)[1] in self._included_suffixes:
                     result_entries.append(''.join([self._result_html_prefix,
-                                                   self._link_str % (fp,fn),
+                                                   self.link_str % (fp,fn),
                                                    self._result_html_suffix]))
         return '\n'.join(result_entries)