How to get the length of a unicode string? [duplicate] - python

given a character like "✮" (\xe2\x9c\xae), for example, can be others like "Σ", "д" or "Λ") I want to find the "actual" length that character takes when printed onscreen
for example
len("✮")
len("\xe2\x9c\xae")
both return 3, but it should be 1

You may try like this:
unicodedata.normalize('NFC', u'✮')
len(u"✮")
UTF-8 is an unicode encoding which uses more than one byte for special characters. Check unicodedata.normalize()

My answer to a similar question:
You are looking for the rendering width from the current output context. For graphical UIs, there is usually a method to directly query this information; for text environments, all you can do is guess what a conformant rendering engine would probably do, and hope that the actual engine matches your expectations.

Related

How to transform the emoji code to the unicode? [duplicate]

I'm trying to build a way to find emojis in twitter and relate them to the unicode table that one can find in unicode.org but I'm finding hard to identify them because of what I think are encoding problems or simply my misunderstanding on this topic. In short, what I did is build a "library" of emojis from the table found in http://www.unicode.org/emoji/charts/full-emoji-list.html that contains the title and the code point (code) of the emoji. I scrapped this in R with the library rvest.
The problem comes when I grab the information from twitter with the twitteR API in R. As the codes for the emojis do not look at all like the ones in this table.
Let's have an example with the emoji of the 100 (one hundred points) red icon. This is the number 1468 in the before linked table and its code point code is:
U+1F4AF
Now, when I grab it from twitter, first of all it is shown like this in the status class that the API has builtin to work with the tweets.
\xed��\xed��
Then, once I convert it to a dataframe, I do it also with a builtin function from the twitter API. For example:
tweet$toDataFrame()
The emoji becomes this:
<ed><U+00A0><U+00BD><ed><U+00B2><U+00AF>
I tried to convert it with the function iconv in R, with the following code:
iconv(tweet$text, from="UTF-8", to="ASCII", "byte)
and I only manage to make it look like this:
<ed><a0><bd><ed><b2><af>
So, wrapping up and at the end of my tests, I got to the following results:
<ed><a0><bd><ed><b2><af>
<ed><U+00A0><U+00BD><ed><U+00B2><U+00AF>
\xed��\xed��
None of which look like the code point specified by the table:
U+1F4AF
Is there any possibility to transform between the two strings?
What am I missing? Why is twitter returning this information for emojis?
I didn't know anything about enconding before, but after days of reading I think I know what is going on. I don't understand perfectly how the encoding for emoji works, but I stumbled upon the same problem and solved it.
You want to map \xed��\xed�� to its name-decoded version: hundred points. A sensible way could be to scrape a dictionary online and use a key, such as Unicode, to replace it. In this case it would be U+1F4AF.
The conversions you show are not different encodings but different notation for the same encoded emoji:
as.data.frame(tweet) returns <ed><U+00A0><U+00BD><ed><U+00B2><U+00AF>.
iconv(tweet, from="UTF-8", to="ASCII", "byte") returns <ed><a0><bd><ed><b2><af>.
So using Unicode directly isn't feasible. Another way could be to use a dictionary that already encodes emoji in the <ed>...<ed>... way like the one here: emoji list. Voilà! Only her list is incomplete because it comes from
a dictionary that contains fewer emoticons.
The fast solution is to simply scrape a more complete dictionary and map the <ed>...<ed>... with its corresponding english text translation. I have done that already and posted here.
Although the fact that nobody else posted a list with the proper encoding bugged me. In fact, most dictionaries I found had an UTF-8 encoding using not an <ed>...<ed>... representation but rather <f0>.... It turns out they are both correct UTF-8 encodings for the same unicode U+1F4AF only the Bytes are read differently.
Long answer. The tweet is read in UTF-16 and then converted to UTF-8, and here is where conversions diverge. When the read is done by pairs of bytes the result will be UTF-8 <ed>...<ed>..., when it is read by chunks of four bytes the result will be UTF-8 <f0>... (Why is this? I don't fully understand, but I suspect it has something to do with the architecture of your processor).
So a slower (but more conscious) way to solve your problem is to scrape the <f0>... dictionary, convert it to UTF-16, convert it back to UTF-8 by pairs and you'll end up with two <ed>.... These two <ed>... is known as the low-high surrogate pair representation for the Unicode U+xxxxx.
As an example:
unicode <- 0x1F4Af
# Multibyte Version
intToUtf8(unicode)
# Byte-pair Version
hilo <- unicode2hilo(unicode)
intToUtf8(hilo)
Returns:
[1] "\xf0\u009f\u0092�"
[1] "\xed��\xed��"
Which, again, using iconv(..., 'utf-8', 'latin1', 'byte'), is the same as:
[1] "<f0><9f><92><af>"
[1] "<ed><a0><bd><ed><b2><af>"
PS1.:
Function unicode2hilo is a simple linear transformation of hi-lo to unicode
unicode2hilo <- function(unicode){
hi = floor((unicode - 0x10000)/0x400) + 0xd800
lo = (unicode - 0x10000) + 0xdc00 - (hi-0xd800)*0x400
hilo = paste('0x', as.hexmode(c(hi,lo)), sep = '')
return(hilo)
}
hilo2unicode <- function(hi,lo){
unicode = (hi - 0xD800) * 0x400 + lo - 0xDC00 + 0x10000
unicode = paste('0x', as.hexmode(unicode), sep = '')
return(unicode)
}
PS2.:
I would recommend using iconv(tweet, 'UTF-8', 'latin1', 'byte') to preserve special characters like áäà.
PS3.:
To replace the emoji with its english text, tag, hash, or anything you want to map it to, I would suggest using DFS in a graph of emojis because there are some emojis whose unicode is the concatenation of other simpler unicodes (i.e. <f0><9f><a4><b8><e2><80><8d><e2><99><82><ef><b8><8f> is a man cartwheeling, while independently <f0><9f><a4><b8> is person cartwheeling, <e2><80><8d> is nothing, <e2><99><82> is a male sign, and <ef><b8><8f> is nothing) and while man cartwheeling and person cartwheeling male sign are obviously semantically related, I prefer the more faithfull translation.
The answer provided by Felipe Suárez Colmenares is excellent because it describes the mechanics of this issue, but I wanted to point you here, which is a dictionary I made with the < ed > R encoding specifically for Twitter. I also have code on how to go through and identify prose versions of emojis. Thought this might be easier for people who stumble into this problem in the future. The dictionary is up to date to the most recent Unicode version (9) and once the even newer one comes out I'll update it then too.
Please try type this: iconv(tweet$text, "latin1", "ASCII", sub="")
There you have also similar discussion:
Emoticons in Twitter Sentiment Analysis in r
Regards,
Magda

Formatting text that is meant to be replaced

This is a rather generic question, but I have a textfile that I want to edit using a script.
What are some ways to format text, so that it will visually stand out but still be recognized by my script?
It works fine when I use text_to_be_replaced, but it is hard to find when you have a large file.
Tried searching, and it seems that the common ways are:
%text_to_be_replaced%
<text_to_be_replaced>
$(text_to_be_replaced)
But maybe there is a commonly used/widely accepted way to format text for visibility?
The language the script is written in is python, if that matters... but I'm looking for a more-or-less generic soluting which will work 90% of the time.
I'm not aware of any generic standard here, but if it's meant to be replaced, you can use the new string formatting method as follows:
string = 'some text {add_text_here} some more text'
Then to replace it when you need to:
value = 'formatted'
string = string.format(add_text_here=value)
Now print it out:
>>> string
'some text formatted some more text'
In fact, this quite neat at the addition of curly {brackets} around the text that needs to be replaced also may make it stand out a little.
At first I thought that {{curly braces}} would be fine, but than I went with $ALLCAPS.
First of all, caps really stands out, while lowercase may be confused with the rest of the code.
And while it $REALLYSTANDSOUT, it shouldn't cause any problems, since it's just a "bookmark" in a text file, and will be replaced with the appropriate stuff determined by the script.

Is it possible to suppress Python's escape sequence processing on a given string without using the raw specifier?

Conclusion: It's impossible to override or disable Python's built-in escape sequence processing, such that, you can skip using the raw prefix specifier. I dug into Python's internals to figure this out. So if anyone tries designing objects that work on complex strings (like regex) as part of some kind of framework, make sure to specify in the docstrings that string arguments to the object's __init__() MUST include the r prefix!
Original question: I am finding it a bit difficult to force Python to not "change" anything about a user-inputted string, which may contain among other things, regex or escaped hexadecimal sequences. I've already tried various combinations of raw strings, .encode('string-escape') (and its decode counterpart), but I can't find the right approach.
Given an escaped, hexadecimal representation of the Documentation IPv6 address 2001:0db8:85a3:0000:0000:8a2e:0370:7334, using .encode(), this small script (called x.py):
#!/usr/bin/env python
class foo(object):
__slots__ = ("_bar",)
def __init__(self, input):
if input is not None:
self._bar = input.encode('string-escape')
else:
self._bar = "qux?"
def _get_bar(self): return self._bar
bar = property(_get_bar)
#
x = foo("\x20\x01\x0d\xb8\x85\xa3\x00\x00\x00\x00\x8a\x2e\x03\x70\x73\x34")
print x.bar
Will yield the following output when executed:
$ ./x.py
\x01\r\xb8\x85\xa3\x00\x00\x00\x00\x8a.\x03ps4
Note the \x20 got converted to an ASCII space character, along with a few others. This is basically correct due to Python processing the escaped hex sequences and converting them to their printable ASCII values.
This can be solved if the initializer to foo() was treated as a raw string (and the .encode() call removed), like this:
x = foo(r"\x20\x01\x0d\xb8\x85\xa3\x00\x00\x00\x00\x8a\x2e\x03\x70\x73\x34")
However, my end goal is to create a kind of framework that can be used and I want to hide these kinds of "implementation details" from the end user. If they called foo() with the above IPv6 address in escaped hexadecimal form (without the raw specifier) and immediately print it back out, they should get back exactly what they put in w/o knowing or using the raw specifier. So I need to find a way to have foo's __init__() do whatever processing is necessary to enable that.
Edit: Per this SO question, it seems it's a defect of Python, in that it always performs some kind of escape sequence processing. There does not appear to be any kind of facility to completely turn off escape sequence processing, even temporarily. Sucks. I guess I am going to have to research subclassing str to create something like rawstr that intelligently determines what escape sequences Python processed in a string, and convert them back to their original format. This is not going to be fun...
Edit2: Another example, given the sample regex below:
"^.{0}\xcb\x00\x71[\x00-\xff]"
If I assign this to a var or pass it to a function without using the raw specifier, the \x71 gets converted to the letter q. Even if I add .encode('string-escape') or .replace('\\', '\\\\'), the escape sequences are still processed. thus resulting in this output:
"^.{0}\xcb\x00q[\x00-\xff]"
How can I stop this, again, without using the raw specifier? Is there some way to "turn off" the escape sequence processing or "revert" it after the fact thus that the q turns back into \x71? Is there a way to process the string and escape the backslashes before the escape sequence processing happens?
I think you have an understandable confusion about a difference between Python string literals (source code representation), Python string objects in memory, and how that objects can be printed (in what format they can be represented in the output).
If you read some bytes from a file into a bytestring you can write them back as is.
r"" exists only in source code there is no such thing at runtime i.e., r"\x" and "\\x" are equal, they may even be the exact same string object in memory.
To see that input is not corrupted, you could print each byte as an integer:
print " ".join(map(ord, raw_input("input something")))
Or just echo as is (there could be a difference but it is unrelated to your "string-escape" issue):
print raw_input("input something")
Identity function:
def identity(obj):
return obj
If you do nothing to the string then your users will receive the exact same object back. You can provide examples in the docs what you consider a concise readable way to represent input string as Python literals. If you find confusing to work with binary strings such as "\x20\x01" then you could accept ascii hex-representation instead: "2001" (you could use binascii.hexlify/unhexlify to convert one to another).
The regex case is more complex because there are two languages:
Escapes sequences are interpreted by Python according to its string literal syntax
Regex engine interprets the string object as a regex pattern that also has its own escape sequences
I think you will have to go the join route.
Here's an example:
>>> m = {chr(c): '\\x{0}'.format(hex(c)[2:].zfill(2)) for c in xrange(0,256)}
>>>
>>> x = "\x20\x01\x0d\xb8\x85\xa3\x00\x00\x00\x00\x8a\x2e\x03\x70\x73\x34"
>>> print ''.join(map(m.get, x))
\x20\x01\x0d\xb8\x85\xa3\x00\x00\x00\x00\x8a\x2e\x03\x70\x73\x34
I'm not entirely sure why you need that though. If your code needs to interact with other pieces of code, I'd suggest that you agree on a defined format, and stick to it.

How can I filter Emoji characters from my input so I can save in MySQL <5.5?

I have a Django app that takes tweet data from Twitter's API and saves it in a MySQL database. As far as I know (I'm still getting my head around the finer points of character encoding) I'm using UTF-8 everywhere, including MySQL encoding and collation, which works fine except when a tweet contains Emoji characters, which I understand use a four-byte encoding. Trying to save them produces the following warnings from Django:
/home/biggleszx/.virtualenvs/myvirtualenv/lib/python2.6/site-packages/django/db/backends/mysql/base.py:86: Warning: Incorrect string value: '\xF0\x9F\x98\xAD I...' for column 'text' at row 1
return self.cursor.execute(query, args)
I'm using MySQL 5.1, so using utf8mb4 isn't an option unless I upgrade to 5.5, which I'd rather not just yet (also from what I've read, Django's support for this isn't quite production-ready, though this might no longer be accurate). I've also seen folks advising the use of BLOB instead of TEXT on affected columns, which I'd also rather not do as I figure it would harm performance.
My question is, then, assuming I'm not too bothered about 100% preservation of the tweet contents, is there a way I can filter out all Emoji characters and replace them with a non-multibyte character, such as the venerable WHITE MEDIUM SMALL SQUARE (U+25FD)? I figure this is the easiest way to save that data given my current setup, though if I'm missing another obvious solution, I'd love to hear it!
FYI, I'm using the stock Python 2.6.5 on Ubuntu 10.04.4 LTS. sys.maxunicode is 1114111, so it's a UCS-4 build.
Thanks for reading.
So it turns out this has been answered a few times, I just hadn't quite got the right Google-fu to find the existing questions.
Python, convert 4-byte char to avoid MySQL error "Incorrect string value:"
Warning raised by inserting 4-byte unicode to mysql
Thanks to Martijn Pieters, the solution came from the world of regular expressions, specifically this code (based on his answer to the first link above):
import re
try:
# UCS-4
highpoints = re.compile(u'[\U00010000-\U0010ffff]')
except re.error:
# UCS-2
highpoints = re.compile(u'[\uD800-\uDBFF][\uDC00-\uDFFF]')
# mytext = u'<some string containing 4-byte chars>'
mytext = highpoints.sub(u'\u25FD', mytext)
The character I'm replacing with is the WHITE MEDIUM SMALL SQUARE (U+25FD), FYI, but could be anything.
For those unfamiliar with UCS, like me, this is a system for Unicode conversion and a given build of Python will include support for either the UCS-2 or UCS-4 variant, each of which has a different upper bound on character support.
With the addition of this code, the strings seem to persist in MySQL 5.1 just fine.
Hope this helps anyone else in the same situation!
I tryied the solution by BigglesZX and its wasn't woring for the emoji of the heart (❤) after reading the [emoji's wikipedia article][1] I've seen that the regular expression is not covering all the emojis while also covering other range of unicode that are not emojis.
The following code create the 5 regular expressions that cover the 5 emoji blocks in the standard:
emoji_symbols_pictograms = re.compile(u'[\U0001f300-\U0001f5fF]')
emoji_emoticons = re.compile(u'[\U0001f600-\U0001f64F]')
emoji_transport_maps = re.compile(u'[\U0001f680-\U0001f6FF]')
emoji_symbols = re.compile(u'[\U00002600-\U000026FF]')
emoji_dingbats = re.compile(u'[\U00002700-\U000027BF]')
Those blocks could be merged in three blocks (UCS-4):
emoji_block0 = re.compile(u'[\U00002600-\U000027BF]')
emoji_block1 = re.compile(u'[\U0001f300-\U0001f64F]')
emoji_block2 = re.compile(u'[\U0001f680-\U0001f6FF]')
Their equivalents in UCS-2 are:
emoji_block0 = re.compile(u'[\u2600-\u27BF]')
emoji_block1 = compile(u'[\uD83C][\uDF00-\uDFFF]')
emoji_block1b = compile(u'[\uD83D][\uDC00-\uDE4F]')
emoji_block2 = re.compile(u'[\uD83D][\uDE80-\uDEFF]')
So finally we can define a single regular expression with all the cases together:
import re
try:
# UCS-4
highpoints = re.compile(u'([\U00002600-\U000027BF])|([\U0001f300-\U0001f64F])|([\U0001f680-\U0001f6FF])')
except re.error:
# UCS-2
highpoints = re.compile(u'([\u2600-\u27BF])|([\uD83C][\uDF00-\uDFFF])|([\uD83D][\uDC00-\uDE4F])|([\uD83D][\uDE80-\uDEFF])')
# mytext = u'<some string containing 4-byte chars>'
mytext = highpoints.sub(u'\u25FD', mytext)
I found out there another regular expresion that is able to identify the emojis.
This the regex is provided by the team at instagram-enginnering blog
u"(?<!&)#(\w|(?:[\xA9\xAE\u203C\u2049\u2122\u2139\u2194-\u2199\u21A9\u21AA\u231A\u231B\u2328\u2388\u23CF\u23E9-\u23F3\u23F8-\u23FA\u24C2\u25AA\u25AB\u25B6\u25C0\u25FB-\u25FE\u2600-\u2604\u260E\u2611\u2614\u2615\u2618\u261D\u2620\u2622\u2623\u2626\u262A\u262E\u262F\u2638-\u263A\u2648-\u2653\u2660\u2663\u2665\u2666\u2668\u267B\u267F\u2692-\u2694\u2696\u2697\u2699\u269B\u269C\u26A0\u26A1\u26AA\u26AB\u26B0\u26B1\u26BD\u26BE\u26C4\u26C5\u26C8\u26CE\u26CF\u26D1\u26D3\u26D4\u26E9\u26EA\u26F0-\u26F5\u26F7-\u26FA\u26FD\u2702\u2705\u2708-\u270D\u270F\u2712\u2714\u2716\u271D\u2721\u2728\u2733\u2734\u2744\u2747\u274C\u274E\u2753-\u2755\u2757\u2763\u2764\u2795-\u2797\u27A1\u27B0\u27BF\u2934\u2935\u2B05-\u2B07\u2B1B\u2B1C\u2B50\u2B55\u3030\u303D\u3297\u3299]|\uD83C[\uDC04\uDCCF\uDD70\uDD71\uDD7E\uDD7F\uDD8E\uDD91-\uDD9A\uDE01\uDE02\uDE1A\uDE2F\uDE32-\uDE3A\uDE50\uDE51\uDF00-\uDF21\uDF24-\uDF93\uDF96\uDF97\uDF99-\uDF9B\uDF9E-\uDFF0\uDFF3-\uDFF5\uDFF7-\uDFFF]|\uD83D[\uDC00-\uDCFD\uDCFF-\uDD3D\uDD49-\uDD4E\uDD50-\uDD67\uDD6F\uDD70\uDD73-\uDD79\uDD87\uDD8A-\uDD8D\uDD90\uDD95\uDD96\uDDA5\uDDA8\uDDB1\uDDB2\uDDBC\uDDC2-\uDDC4\uDDD1-\uDDD3\uDDDC-\uDDDE\uDDE1\uDDE3\uDDEF\uDDF3\uDDFA-\uDE4F\uDE80-\uDEC5\uDECB-\uDED0\uDEE0-\uDEE5\uDEE9\uDEEB\uDEEC\uDEF0\uDEF3]|\uD83E[\uDD10-\uDD18\uDD80-\uDD84\uDDC0]|(?:0\u20E3|1\u20E3|2\u20E3|3\u20E3|4\u20E3|5\u20E3|6\u20E3|7\u20E3|8\u20E3|9\u20E3|#\u20E3|\\*\u20E3|\uD83C(?:\uDDE6\uD83C(?:\uDDEB|\uDDFD|\uDDF1|\uDDF8|\uDDE9|\uDDF4|\uDDEE|\uDDF6|\uDDEC|\uDDF7|\uDDF2|\uDDFC|\uDDE8|\uDDFA|\uDDF9|\uDDFF|\uDDEA)|\uDDE7\uD83C(?:\uDDF8|\uDDED|\uDDE9|\uDDE7|\uDDFE|\uDDEA|\uDDFF|\uDDEF|\uDDF2|\uDDF9|\uDDF4|\uDDE6|\uDDFC|\uDDFB|\uDDF7|\uDDF3|\uDDEC|\uDDEB|\uDDEE|\uDDF6|\uDDF1)|\uDDE8\uD83C(?:\uDDF2|\uDDE6|\uDDFB|\uDDEB|\uDDF1|\uDDF3|\uDDFD|\uDDF5|\uDDE8|\uDDF4|\uDDEC|\uDDE9|\uDDF0|\uDDF7|\uDDEE|\uDDFA|\uDDFC|\uDDFE|\uDDFF|\uDDED)|\uDDE9\uD83C(?:\uDDFF|\uDDF0|\uDDEC|\uDDEF|\uDDF2|\uDDF4|\uDDEA)|\uDDEA\uD83C(?:\uDDE6|\uDDE8|\uDDEC|\uDDF7|\uDDEA|\uDDF9|\uDDFA|\uDDF8|\uDDED)|\uDDEB\uD83C(?:\uDDF0|\uDDF4|\uDDEF|\uDDEE|\uDDF7|\uDDF2)|\uDDEC\uD83C(?:\uDDF6|\uDDEB|\uDDE6|\uDDF2|\uDDEA|\uDDED|\uDDEE|\uDDF7|\uDDF1|\uDDE9|\uDDF5|\uDDFA|\uDDF9|\uDDEC|\uDDF3|\uDDFC|\uDDFE|\uDDF8|\uDDE7)|\uDDED\uD83C(?:\uDDF7|\uDDF9|\uDDF2|\uDDF3|\uDDF0|\uDDFA)|\uDDEE\uD83C(?:\uDDF4|\uDDE8|\uDDF8|\uDDF3|\uDDE9|\uDDF7|\uDDF6|\uDDEA|\uDDF2|\uDDF1|\uDDF9)|\uDDEF\uD83C(?:\uDDF2|\uDDF5|\uDDEA|\uDDF4)|\uDDF0\uD83C(?:\uDDED|\uDDFE|\uDDF2|\uDDFF|\uDDEA|\uDDEE|\uDDFC|\uDDEC|\uDDF5|\uDDF7|\uDDF3)|\uDDF1\uD83C(?:\uDDE6|\uDDFB|\uDDE7|\uDDF8|\uDDF7|\uDDFE|\uDDEE|\uDDF9|\uDDFA|\uDDF0|\uDDE8)|\uDDF2\uD83C(?:\uDDF4|\uDDF0|\uDDEC|\uDDFC|\uDDFE|\uDDFB|\uDDF1|\uDDF9|\uDDED|\uDDF6|\uDDF7|\uDDFA|\uDDFD|\uDDE9|\uDDE8|\uDDF3|\uDDEA|\uDDF8|\uDDE6|\uDDFF|\uDDF2|\uDDF5|\uDDEB)|\uDDF3\uD83C(?:\uDDE6|\uDDF7|\uDDF5|\uDDF1|\uDDE8|\uDDFF|\uDDEE|\uDDEA|\uDDEC|\uDDFA|\uDDEB|\uDDF4)|\uDDF4\uD83C\uDDF2|\uDDF5\uD83C(?:\uDDEB|\uDDF0|\uDDFC|\uDDF8|\uDDE6|\uDDEC|\uDDFE|\uDDEA|\uDDED|\uDDF3|\uDDF1|\uDDF9|\uDDF7|\uDDF2)|\uDDF6\uD83C\uDDE6|\uDDF7\uD83C(?:\uDDEA|\uDDF4|\uDDFA|\uDDFC|\uDDF8)|\uDDF8\uD83C(?:\uDDFB|\uDDF2|\uDDF9|\uDDE6|\uDDF3|\uDDE8|\uDDF1|\uDDEC|\uDDFD|\uDDF0|\uDDEE|\uDDE7|\uDDF4|\uDDF8|\uDDED|\uDDE9|\uDDF7|\uDDEF|\uDDFF|\uDDEA|\uDDFE)|\uDDF9\uD83C(?:\uDDE9|\uDDEB|\uDDFC|\uDDEF|\uDDFF|\uDDED|\uDDF1|\uDDEC|\uDDF0|\uDDF4|\uDDF9|\uDDE6|\uDDF3|\uDDF7|\uDDF2|\uDDE8|\uDDFB)|\uDDFA\uD83C(?:\uDDEC|\uDDE6|\uDDF8|\uDDFE|\uDDF2|\uDDFF)|\uDDFB\uD83C(?:\uDDEC|\uDDE8|\uDDEE|\uDDFA|\uDDE6|\uDDEA|\uDDF3)|\uDDFC\uD83C(?:\uDDF8|\uDDEB)|\uDDFD\uD83C\uDDF0|\uDDFE\uD83C(?:\uDDF9|\uDDEA)|\uDDFF\uD83C(?:\uDDE6|\uDDF2|\uDDFC))))[\ufe00-\ufe0f\u200d]?)+
Source:
http://instagram-engineering.tumblr.com/post/118304328152/emojineering-part-2-implementing-hashtag-emoji
note: I add another answer as this one is not complemetary to my previous answer here.
i am using json encoder function that encode the input.
this function is used for dict encoding (to convert it to string) on json.dumps. (so we need to do some edit to the response - remove the ' " ')
this enabled me to save emoji to mysql, and present it (at web):
# encode input
from json.encoder import py_encode_basestring_ascii
name = py_encode_basestring_ascii(name)[1:-1]
# save
YourModel.name = name
name.save()

splitting unicode string into words

I am trying to split a Unicode string into words (simplistic), like this:
print re.findall(r'(?u)\w+', "раз два три")
What I expect to see is:
['раз','два','три']
But what I really get is:
['\xd1', '\xd0', '\xd0', '\xd0', '\xd0\xb2\xd0', '\xd1', '\xd1', '\xd0']
What am I doing wrong?
Edit:
If I use u in front of the string:
print re.findall(r'(?u)\w+', u"раз два три")
I get:
[u'\u0440\u0430\u0437', u'\u0434\u0432\u0430', u'\u0442\u0440\u0438']
Edit 2:
Aaaaand it seems like I should have read docs first:
print re.findall(r'(?u)\w+', u"раз два три")[0].encode('utf-8')
Will give me:
раз
Just to make sure though, does that sound like a proper way of approaching it?
You're actually getting the stuff you expect in the unicode case. You only think you are not because of the weird escaping due to the fact that you're looking at the reprs of the strings, not not printing their unescaped values. (This is just how lists are displayed.)
>>> words = [u'\u0440\u0430\u0437', u'\u0434\u0432\u0430', u'\u0442\u0440\u0438']
>>> for w in words:
... print w # This uses the terminal encoding -- _only_ utilize interactively
...
раз
два
три
>>> u'раз' == u'\u0440\u0430\u0437'
True
Don't miss my remark about printing these unicode strings. Normally if you were going to send them to screen, a file, over the wire, etc. you need to manually encode them into the correct encoding. When you use print, Python tries to leverage your terminal's encoding, but it can only do that if there is a terminal. Because you don't generally know if there is one, you should only rely on this in the interactive interpreter, and always encode to the right encoding explicitly otherwise.
In this simple splitting-on-whitespace approach, you might not want to use regex at all but simply to use the unicode.split method.
>>> u"раз два три".split()
[u'\u0440\u0430\u0437', u'\u0434\u0432\u0430', u'\u0442\u0440\u0438']
Your top (bytestring) example does not work because re basically assumes all bytestrings are ASCII for its semantics, but yours was not. Using unicode strings allows you to get the right semantics for your alphabet and locale. As much as possible, textual data should always be represented using unicode rather than str.

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