unicode hammer

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This is the crudest, brute force conversion of UNICODE to 7-bit ASCII strings. This is for when you don't want to have to think very hard about Python UNICODE conversions. This bypasses all the usual Python UNICODE encoding stuff and just stomps on the string. Obviously, this doesn't always work very well.

#!/usr/bin/env python
"""
latin1_to_ascii -- The UNICODE Hammer -- AKA "The Stupid American"

This takes a UNICODE string and replaces Latin-1 characters with
something equivalent in 7-bit ASCII. This returns a plain ASCII string. 
This function makes a best effort to convert Latin-1 characters into 
ASCII equivalents. It does not just strip out the Latin1 characters.
All characters in the standard 7-bit ASCII range are preserved.
In the 8th bit range, all the Latin-1 accented letters are converted to
unaccented equivalents. Most symbol characters are converted to
something meaningful. Anything not converted is deleted.

Background:

One of my clients gets address data from Europe, but most of their systems 
cannot handle Latin-1 characters. With all due respect to the umlaut,
scharfes s, cedilla, and all the other fine accented characters of Europe, 
all I needed to do was to prepare addresses for a shipping system.
After getting headaches trying to deal with this problem using Python's 
built-in UNICODE support I gave up and decided to use some brute force.
This function converts all accented letters to their unaccented equivalents. 
I realize this is dirty, but for my purposes, the mail gets delivered.
"""

def latin1_to_ascii (unicrap):
    """This takes a UNICODE string and replaces Latin-1 characters with
        something equivalent in 7-bit ASCII. It returns a plain ASCII string. 
        This function makes a best effort to convert Latin-1 characters into 
        ASCII equivalents. It does not just strip out the Latin-1 characters.
        All characters in the standard 7-bit ASCII range are preserved. 
        In the 8th bit range, all the Latin-1 accented letters are converted
        to unaccented equivalents. Most symbol characters are converted to
        something meaningful. Anything not converted is deleted.
    """
    xlate={0xc0:'A', 0xc1:'A', 0xc2:'A', 0xc3:'A', 0xc4:'A', 0xc5:'A',
        0xc6:'Ae', 0xc7:'C',
        0xc8:'E', 0xc9:'E', 0xca:'E', 0xcb:'E',
        0xcc:'I', 0xcd:'I', 0xce:'I', 0xcf:'I',
        0xd0:'Th', 0xd1:'N',
        0xd2:'O', 0xd3:'O', 0xd4:'O', 0xd5:'O', 0xd6:'O', 0xd8:'O',
        0xd9:'U', 0xda:'U', 0xdb:'U', 0xdc:'U',
        0xdd:'Y', 0xde:'th', 0xdf:'ss',
        0xe0:'a', 0xe1:'a', 0xe2:'a', 0xe3:'a', 0xe4:'a', 0xe5:'a',
        0xe6:'ae', 0xe7:'c',
        0xe8:'e', 0xe9:'e', 0xea:'e', 0xeb:'e',
        0xec:'i', 0xed:'i', 0xee:'i', 0xef:'i',
        0xf0:'th', 0xf1:'n',
        0xf2:'o', 0xf3:'o', 0xf4:'o', 0xf5:'o', 0xf6:'o', 0xf8:'o',
        0xf9:'u', 0xfa:'u', 0xfb:'u', 0xfc:'u',
        0xfd:'y', 0xfe:'th', 0xff:'y',
        0xa1:'!', 0xa2:'{cent}', 0xa3:'{pound}', 0xa4:'{currency}',
        0xa5:'{yen}', 0xa6:'|', 0xa7:'{section}', 0xa8:'{umlaut}',
        0xa9:'{C}', 0xaa:'{^a}', 0xab:'<<', 0xac:'{not}',
        0xad:'-', 0xae:'{R}', 0xaf:'_', 0xb0:'{degrees}',
        0xb1:'{+/-}', 0xb2:'{^2}', 0xb3:'{^3}', 0xb4:"'",
        0xb5:'{micro}', 0xb6:'{paragraph}', 0xb7:'*', 0xb8:'{cedilla}',
        0xb9:'{^1}', 0xba:'{^o}', 0xbb:'>>', 
        0xbc:'{1/4}', 0xbd:'{1/2}', 0xbe:'{3/4}', 0xbf:'?',
        0xd7:'*', 0xf7:'/'
        }

    r = ''
    for i in unicrap:
        if xlate.has_key(ord(i)):
            r += xlate[ord(i)]
        elif ord(i) >= 0x80:
            pass
        else:
            r += str(i)
    return r

if __name__ == '__main__':
    s = unicode('','latin-1')
    for c in range(32,256):
        if c != 0x7f:
            s = s + unicode(chr(c),'latin-1')
    plain_ascii = latin1_to_ascii(s)
    
    print 'INPUT type:', type(s)
    print 'INPUT:'
    print s.encode('latin-1')
    print
    print 'OUTPUT type:', type(plain_ascii)
    print 'OUTPUT:'
    print plain_ascii