1 files changed, 127 insertions, 0 deletions
diff --git a/Demo/tkinter/guido/regexdemo.py b/Demo/tkinter/guido/regexdemo.py
new file mode 100644
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+++ b/Demo/tkinter/guido/regexdemo.py
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+"""Basic regular expression demostration facility.
+
+This displays a window with two type-in boxes.  In the top box, you enter a 
+regular expression.  In the bottom box, you enter a string.  The first 
+match in the string of the regular expression is highlighted with a yellow 
+background (or red if the match is empty -- then the character at the match 
+is highlighted).  The highlighting is continuously updated.  At the bottom 
+are a number of checkboxes which control the regular expression syntax used 
+(see the regex_syntax module for descriptions).  When there's no match, or 
+when the regular expression is syntactically incorrect, an error message is
+displayed.
+
+"""
+
+from Tkinter import *
+import regex
+import regex_syntax
+
+class RegexDemo:
+	
+	def __init__(self, master):
+		self.master = master
+		self.topframe = Frame(self.master)
+		self.topframe.pack(fill=X)
+		self.promptdisplay = Label(self.topframe, text="Enter a string:")
+		self.promptdisplay.pack(side=LEFT)
+		self.statusdisplay = Label(self.topframe, text="", anchor=W)
+		self.statusdisplay.pack(side=LEFT, fill=X)
+		self.regexdisplay = Entry(self.master)
+		self.regexdisplay.pack(fill=X)
+		self.regexdisplay.focus_set()
+		self.labeldisplay = Label(self.master, anchor=W,
+			text="Enter a string:")
+		self.labeldisplay.pack(fill=X)
+		self.labeldisplay.pack(fill=X)
+		self.stringdisplay = Text(self.master, width=60, height=4)
+		self.stringdisplay.pack(fill=BOTH, expand=1)
+		self.stringdisplay.tag_configure("hit", background="yellow")
+		self.addoptions()
+		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 (	'RE_NO_BK_PARENS',
+				'RE_NO_BK_VBAR',
+				'RE_BK_PLUS_QM',
+				'RE_TIGHT_VBAR',
+				'RE_NEWLINE_OR',
+				'RE_CONTEXT_INDEP_OPS'):
+			if len(self.boxes) % 3 == 0:
+				frame = Frame(self.master)
+				frame.pack(fill=X)
+				self.frames.append(frame)
+			val = getattr(regex_syntax, name)
+			var = IntVar()
+			box = Checkbutton(frame,
+				variable=var, text=name,
+				offvalue=0, onvalue=val,
+				command=self.newsyntax)
+			box.pack(side=LEFT)
+			self.boxes.append(box)
+			self.vars.append(var)
+	
+	def newsyntax(self):
+		syntax = 0
+		for var in self.vars:
+			syntax = syntax | var.get()
+		regex.set_syntax(syntax)
+		self.recompile()
+	
+	def recompile(self, event=None):
+		try:
+			self.compiled = regex.compile(self.regexdisplay.get())
+			self.statusdisplay.config(text="")
+		except regex.error, msg:
+			self.compiled = None
+			self.statusdisplay.config(text="regex.error: %s" % str(msg))
+		self.reevaluate()
+	
+	def reevaluate(self, event=None):
+		try:
+			self.stringdisplay.tag_remove("hit", "1.0", END)
+		except TclError:
+			pass
+		if not self.compiled:
+			return
+		text = self.stringdisplay.get("1.0", END)
+		i = self.compiled.search(text)
+		if i < 0:
+			self.statusdisplay.config(text="(no match)")
+		else:
+			self.statusdisplay.config(text="")
+			regs = self.compiled.regs
+			first, last = regs[0]
+			if last == first:
+				last = first+1
+				self.stringdisplay.tag_configure("hit",
+					background="red")
+			else:
+				self.stringdisplay.tag_configure("hit",
+					background="yellow")
+			pfirst = "1.0 + %d chars" % first
+			plast = "1.0 + %d chars" % last
+			self.stringdisplay.tag_add("hit", pfirst, plast)
+			self.stringdisplay.yview_pickplace(pfirst)
+
+
+
+# Main function, run when invoked as a stand-alone Python program.
+
+def main():
+    root = Tk()
+    demo = RegexDemo(root)
+    root.protocol('WM_DELETE_WINDOW', root.quit)
+    root.mainloop()
+
+if __name__ == '__main__':
+    main()