1 """Basic regular expression demostration facility (Perl style syntax)."""

     2 

     3 from Tkinter import *

     4 import re

     5 

     6 class ReDemo:

     7 

     8     def __init__(self, master):

     9         self.master = master

    10 

    11         self.promptdisplay = Label(self.master, anchor=W,

    12                 text="Enter a Perl-style regular expression:")

    13         self.promptdisplay.pack(side=TOP, fill=X)

    14 

    15         self.regexdisplay = Entry(self.master)

    16         self.regexdisplay.pack(fill=X)

    17         self.regexdisplay.focus_set()

    18 

    19         self.addoptions()

    20 

    21         self.statusdisplay = Label(self.master, text="", anchor=W)

    22         self.statusdisplay.pack(side=TOP, fill=X)

    23 

    24         self.labeldisplay = Label(self.master, anchor=W,

    25                 text="Enter a string to search:")

    26         self.labeldisplay.pack(fill=X)

    27         self.labeldisplay.pack(fill=X)

    28 

    29         self.showframe = Frame(master)

    30         self.showframe.pack(fill=X, anchor=W)

    31 

    32         self.showvar = StringVar(master)

    33         self.showvar.set("first")

    34 

    35         self.showfirstradio = Radiobutton(self.showframe,

    36                                          text="Highlight first match",

    37                                           variable=self.showvar,

    38                                           value="first",

    39                                           command=self.recompile)

    40         self.showfirstradio.pack(side=LEFT)

    41 

    42         self.showallradio = Radiobutton(self.showframe,

    43                                         text="Highlight all matches",

    44                                         variable=self.showvar,

    45                                         value="all",

    46                                         command=self.recompile)

    47         self.showallradio.pack(side=LEFT)

    48 

    49         self.stringdisplay = Text(self.master, width=60, height=4)

    50         self.stringdisplay.pack(fill=BOTH, expand=1)

    51         self.stringdisplay.tag_configure("hit", background="yellow")

    52 

    53         self.grouplabel = Label(self.master, text="Groups:", anchor=W)

    54         self.grouplabel.pack(fill=X)

    55 

    56         self.grouplist = Listbox(self.master)

    57         self.grouplist.pack(expand=1, fill=BOTH)

    58 

    59         self.regexdisplay.bind('<Key>', self.recompile)

    60         self.stringdisplay.bind('<Key>', self.reevaluate)

    61 

    62         self.compiled = None

    63         self.recompile()

    64 

    65         btags = self.regexdisplay.bindtags()

    66         self.regexdisplay.bindtags(btags[1:] + btags[:1])

    67 

    68         btags = self.stringdisplay.bindtags()

    69         self.stringdisplay.bindtags(btags[1:] + btags[:1])

    70 

    71     def addoptions(self):

    72         self.frames = []

    73         self.boxes = []

    74         self.vars = []

    75         for name in ('IGNORECASE',

    76                      'LOCALE',

    77                      'MULTILINE',

    78                      'DOTALL',

    79                      'VERBOSE'):

    80             if len(self.boxes) % 3 == 0:

    81                 frame = Frame(self.master)

    82                 frame.pack(fill=X)

    83                 self.frames.append(frame)

    84             val = getattr(re, name)

    85             var = IntVar()

    86             box = Checkbutton(frame,

    87                     variable=var, text=name,

    88                     offvalue=0, onvalue=val,

    89                     command=self.recompile)

    90             box.pack(side=LEFT)

    91             self.boxes.append(box)

    92             self.vars.append(var)

    93 

    94     def getflags(self):

    95         flags = 0

    96         for var in self.vars:

    97             flags = flags | var.get()

    98         flags = flags

    99         return flags

   100 

   101     def recompile(self, event=None):

   102         try:

   103             self.compiled = re.compile(self.regexdisplay.get(),

   104                                        self.getflags())

   105             bg = self.promptdisplay['background']

   106             self.statusdisplay.config(text="", background=bg)

   107         except re.error, msg:

   108             self.compiled = None

   109             self.statusdisplay.config(

   110                     text="re.error: %s" % str(msg),

   111                     background="red")

   112         self.reevaluate()

   113 

   114     def reevaluate(self, event=None):

   115         try:

   116             self.stringdisplay.tag_remove("hit", "1.0", END)

   117         except TclError:

   118             pass

   119         try:

   120             self.stringdisplay.tag_remove("hit0", "1.0", END)

   121         except TclError:

   122             pass

   123         self.grouplist.delete(0, END)

   124         if not self.compiled:

   125             return

   126         self.stringdisplay.tag_configure("hit", background="yellow")

   127         self.stringdisplay.tag_configure("hit0", background="orange")

   128         text = self.stringdisplay.get("1.0", END)

   129         last = 0

   130         nmatches = 0

   131         while last <= len(text):

   132             m = self.compiled.search(text, last)

   133             if m is None:

   134                 break

   135             first, last = m.span()

   136             if last == first:

   137                 last = first+1

   138                 tag = "hit0"

   139             else:

   140                 tag = "hit"

   141             pfirst = "1.0 + %d chars" % first

   142             plast = "1.0 + %d chars" % last

   143             self.stringdisplay.tag_add(tag, pfirst, plast)

   144             if nmatches == 0:

   145                 self.stringdisplay.yview_pickplace(pfirst)

   146                 groups = list(m.groups())

   147                 groups.insert(0, m.group())

   148                 for i in range(len(groups)):

   149                     g = "%2d: %r" % (i, groups[i])

   150                     self.grouplist.insert(END, g)

   151             nmatches = nmatches + 1

   152             if self.showvar.get() == "first":

   153                 break

   154 

   155         if nmatches == 0:

   156             self.statusdisplay.config(text="(no match)",

   157                                       background="yellow")

   158         else:

   159             self.statusdisplay.config(text="")

   160 

   161 

   162 # Main function, run when invoked as a stand-alone Python program.

   163 

   164 def main():

   165     root = Tk()

   166     demo = ReDemo(root)

   167     root.protocol('WM_DELETE_WINDOW', root.quit)

   168     root.mainloop()

   169 

   170 if __name__ == '__main__':

   171     main()