[Tutor] Question on regular expressions

[Andrew Robert]

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Hi Everyone,


Thanks for all of your patience on this.

I finally got it to work.


Here is the completed test code showing what is going on.

Not cleaned up yet but it works for proof-of-concept purposes.



#!/usr/bin/python

import re,base64

# Evaluate captured character as hex
def ret_hex(value):
	return '%'+base64.b16encode(value)

# Evaluate the value of whatever was matched
def enc_hex_match(match):
 	return ret_hex(match.group(0))

def ret_ascii(value):
	return base64.b16decode(value)

# Evaluate the value of whatever was matched
def enc_ascii_match(match):

	arg=match.group()

	#remove the artifically inserted % sign
	arg=arg[1:]

	# decode the result
 	return ret_ascii(arg)

def file_encoder():
	# Read each line, pass any matches on line to function for
	# line in file.readlines():
	output=open(r'e:\pycode\sigh.new','wb')
	for line in open(r'e:\pycode\sigh.txt','rb'):
		 output.write( (re.sub('[^\w\s]',enc_hex_match, line)) )
	output.close()


def file_decoder():
	# Read each line, pass any matches on line to function for
	# line in file.readlines():

	output=open(r'e:\pycode\sigh.new2','wb')
	for line in open(r'e:\pycode\sigh.new','rb'):
		output.write(re.sub('%[0-9A-F][0-9A-F]',enc_ascii_match, line))
	output.close()




file_encoder()

file_decoder()
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