1 files changed, 171 insertions, 0 deletions
diff --git a/Tools/demo/redemo.py b/Tools/demo/redemo.py
new file mode 100644
index 0000000..5286332
--- /dev/null
+++ b/Tools/demo/redemo.py
@@ -0,0 +1,171 @@
+"""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 as 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()