#! /usr/bin/env python
"""Basic regular expression demostration facility (Perl style syntax)."""
from Tkinter import *
import re
class ReDemo:
def __init__(self, master):
self.master = master
self.promptdisplay = Label(self.master, anchor=W,
text="Enter a Perl-style regular expression:")
self.promptdisplay.pack(side=TOP, fill=X)
self.regexdisplay = Entry(self.master)
self.regexdisplay.pack(fill=X)
self.regexdisplay.focus_set()
self.addoptions()
self.statusdisplay = Label(self.master, text="", anchor=W)
self.statusdisplay.pack(side=TOP, fill=X)
self.labeldisplay = Label(self.master, anchor=W,
text="Enter a string to search:")
self.labeldisplay.pack(fill=X)
self.labeldisplay.pack(fill=X)
self.showframe = Frame(master)
self.showframe.pack(fill=X, anchor=W)
self.showvar = StringVar(master)
self.showvar.set("first")
self.showfirstradio = Radiobutton(self.showframe,
text="Highlight first match",
variable=self.showvar,
value="first",
command=self.recompile)
self.showfirstradio.pack(side=LEFT)
self.showallradio = Radiobutton(self.showframe,
text="Highlight all matches",
variable=self.showvar,
value="all",
command=self.recompile)
self.showallradio.pack(side=LEFT)
self.stringdisplay = Text(self.master, width=60, height=4)
self.stringdisplay.pack(fill=BOTH, expand=1)
self.stringdisplay.tag_configure("hit", background="yellow")
self.grouplabel = Label(self.master, text="Groups:", anchor=W)
self.grouplabel.pack(fill=X)
self.grouplist = Listbox(self.master)
self.grouplist.pack(expand=1, fill=BOTH)
self.regexdisplay.bind('<Key>', self.recompile)
self.stringdisplay.bind('<Key>', self.reevaluate)
self.compiled = None
self.recompile()
btags = self.regexdisplay.bindtags()
self.regexdisplay.bindtags(btags[1:] + btags[:1])
btags = self.stringdisplay.bindtags()
self.stringdisplay.bindtags(btags[1:] + btags[:1])
def addoptions(self):
self.frames = []
self.boxes = []
self.vars = []
for name in ('IGNORECASE',
'LOCALE',
'MULTILINE',
'DOTALL',
'VERBOSE'):
if len(self.boxes) % 3 == 0:
frame = Frame(self.master)
frame.pack(fill=X)
self.frames.append(frame)
val = getattr(re, name)
var = IntVar()
box = Checkbutton(frame,
variable=var, text=name,
offvalue=0, onvalue=val,
command=self.recompile)
box.pack(side=LEFT)
self.boxes.append(box)
self.vars.append(var)
def getflags(self):
flags = 0
for var in self.vars:
flags = flags | var.get()
flags = flags
return flags
def recompile(self, event=None):
try:
self.compiled = re.compile(self.regexdisplay.get(),
self.getflags())
bg = self.promptdisplay['background']
self.statusdisplay.config(text="", background=bg)
except re.error, msg:
self.compiled = None
self.statusdisplay.config(
text="re.error: %s" % str(msg),
background="red")
self.reevaluate()
def reevaluate(self, event=None):
try:
self.stringdisplay.tag_remove("hit", "1.0", END)
except TclError:
pass
try:
self.stringdisplay.tag_remove("hit0", "1.0", END)
except TclError:
pass
self.grouplist.delete(0, END)
if not self.compiled:
return
self.stringdisplay.tag_configure("hit", background="yellow")
self.stringdisplay.tag_configure("hit0", background="orange")
text = self.stringdisplay.get("1.0", END)
last = 0
nmatches = 0
while last <= len(text):
m = self.compiled.search(text, last)
if m is None:
break
first, last = m.span()
if last == first:
last = first+1
tag = "hit0"
else:
tag = "hit"
pfirst = "1.0 + %d chars" % first
plast = "1.0 + %d chars" % last
self.stringdisplay.tag_add(tag, pfirst, plast)
if nmatches == 0:
self.stringdisplay.yview_pickplace(pfirst)
groups = list(m.groups())
groups.insert(0, m.group())
for i in range(len(groups)):
g = "%2d: %r" % (i, groups[i])
self.grouplist.insert(END, g)
nmatches = nmatches + 1
if self.showvar.get() == "first":
break
if nmatches == 0:
self.statusdisplay.config(text="(no match)",
background="yellow")
else:
self.statusdisplay.config(text="")
# Main function, run when invoked as a stand-alone Python program.
def main():
root = Tk()
demo = ReDemo(root)
root.protocol('WM_DELETE_WINDOW', root.quit)
root.mainloop()
if __name__ == '__main__':
main()