Building profanity filters on mobile: clbuttic sh!t

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BUILDING PROFANITY FILTERS clbuttic sh!t

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Framework Days. IT Saturday. 5.09.2015 INTERNET CENSORSHIP children religion sexual https://en.wikipedia.org/wiki/Censorship

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Framework Days. IT Saturday. 5.09.2015 WHY FILTERING GOOD ETHNICITY PROTECTS CHILDREN RELIGION SEXUAL ORIENTATION

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Framework Days. IT Saturday. 5.09.2015 WHY FILTERING BAD lack of trust to your users their willing to break rules →

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Framework Days. IT Saturday. 5.09.2015

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Framework Days. IT Saturday. 5.09.2015 COCK

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LET’S BUILD FILTER! Framework Days. IT Saturday. 5.09.2015 ﬁlter = list of dirty words + list of replacements + ﬁlter rule

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– George Carlin, 1972 Shit, piss, fuck, cunt, cocksucker, motherfucker, and tits. “Seven Words You Can Never Say on Television” Framework Days. IT Saturday. 5.09.2015

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FILTER RULES Framework Days. IT Saturday. 5.09.2015 1. search by entry psss…

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RANGE OF WORD Framework Days. IT Saturday. 5.09.2015 NSRange range = [text rangeOfString:badWord options:NSCaseInsensitiveSearch]; BOOL hasDirtyWord = [text localizedCaseInsensitiveContainsString:badWord];

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RANGE OF WORD Framework Days. IT Saturday. 5.09.2015 - (NSArray * )rangesOfBadWordsWithSpaceInString:(NSString * )text { __block NSMutableArray * result = [NSMutableArray array]; [self.listOfBadWordsWithSpace enumerateObjectsUsingBlock:^(NSString * badWord, NSUInteger idx, BOOL * stop) { NSRange range = [text rangeOfString:badWord options:NSCaseInsensitiveSearch]; while (range.location != NSNotFound) { [result addObject:[NSValue valueWithRange:range]]; NSRange nextRange = NSMakeRange(range.location + 1, [text length] - range.location - 1); range = [text rangeOfString:badWord options:NSCaseInsensitiveSearch range:nextRange]; } }]; return result; }

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SEARCH BY ENTRY Framework Days. IT Saturday. 5.09.2015 Get your ass down here! The grass around the creek was new, giving it a velvety look. Dusty, his heartless assassin, had found his mate.

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SEARCH BY ENTRY Framework Days. IT Saturday. 5.09.2015 Get your ass down here! The grass around the creek was new, giving it a velvety look. Dusty, his heartless assassin, had found his mate.

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SEARCH BY ENTRY Framework Days. IT Saturday. 5.09.2015 Get your ass down here! The grass around the creek was new, giving it a velvety look. Dusty, his heartless assassin, had found his mate.

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FALSE POSITIVES Framework Days. IT Saturday. 5.09.2015

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Framework Days. IT Saturday. 5.09.2015 Get your ass down here! The grass around the creek was new, giving it a velvety look. Dusty, his heartless assassin, had found his mate. FALSE POSITIVES

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Framework Days. IT Saturday. 5.09.2015 assart assault association assurance ‘ASS’ WORDS harassment hassel hourglass impassable pass passion piassaba preassign 1250 words found http://www.morewords.com/contains/ass/

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Framework Days. IT Saturday. 5.09.2015 ass → butt REPLACEMENT RULES…

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Framework Days. IT Saturday. 5.09.2015 classic → clbuttic …FAILS

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Framework Days. IT Saturday. 5.09.2015

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Framework Days. IT Saturday. 5.09.2015 Constitution → Consbreastution AND FAILS AGAIN… medieval → medireview Tyson Gay → Tyson Homosexual

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FILTER RULES Framework Days. IT Saturday. 5.09.2015 1. search by entry 2. search whole word don’t u know me?

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SEARCH WHOLE WORD Framework Days. IT Saturday. 5.09.2015 NSString * scanned; if ([scanner scanCharactersFromSet:wordCharacters intoString:&scanned]) { if ([wordSet containsObject:[scanned lowercaseString]]) { NSRange range = NSMakeRange(scanner.scanLocation - scanned.length, scanned.length); [result addObject:[NSValue valueWithRange:range]]; } } NSSet * badWordsSet = [NSMutableSet setWithArray:self.listOfBadWords]; NSScanner * scanner = [NSScanner scannerWithString:text]; NSCharacterSet * wordCharacters = [NSCharacterSet alphanumericCharacterSet];

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SEARCH WHOLE WORD Framework Days. IT Saturday. 5.09.2015 Get your ass down here! The grass around the creek was new, giving it a velvety look. Dusty, his heartless assassin, had found his mate.

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SPACE! Framework Days. IT Saturday. 5.09.2015 AND OTHER PUNCTUATION

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Framework Days. IT Saturday. 5.09.2015 Get your a s s down here! You'd probably ﬁre my a.s.s the ﬁrst day on the job. You've covered my a_s_s every time I screwed up. PUNCTUATION

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Framework Days. IT Saturday. 5.09.2015 Get your a s s down here! You'd probably ﬁre my a.s.s the ﬁrst day on the job. You've covered my a_s_s every time I screwed up. PUNCTUATION

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FILTER RULES Framework Days. IT Saturday. 5.09.2015 1. search by entry 2. search whole word 3. handle punctuation don’t tell anyone…

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1337 59341< Framework Days. IT Saturday. 5.09.2015

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L33T SPEAK Framework Days. IT Saturday. 5.09.2015 HOW MANY DIFFERENT SPELLINGS HAS ONE WORD?

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BITCH Framework Days. IT Saturday. 5.09.2015

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B1TCH Framework Days. IT Saturday. 5.09.2015 I → 1 BITCH

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B!TCH Framework Days. IT Saturday. 5.09.2015 I → ! BITCH B1TCH

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BI+CH Framework Days. IT Saturday. 5.09.2015 T → + BITCH B1TCH B!TCH

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I3ITCH Framework Days. IT Saturday. 5.09.2015 B → I3 BITCH B1TCH B!TCH BI+CH

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BITCH B!TCH B1TCH 8ITCH ßITCH 13ITCH L3ITCH BI7CH BI+CH BI†CH BIT[H BIT¢H BIT

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FILTER RULES Framework Days. IT Saturday. 5.09.2015 1. search by entry 2. search whole word 3. handle punctuation 4. handle l33t speak my name is…

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SCUNTHORPE PROBLEM Framework Days. IT Saturday. 5.09.2015 https://en.wikipedia.org/wiki/Scunthorpe_problem

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NICE TITS In 2007, the Royal Society for the Protection of Birds blocked ornithological terms such as cock (male bird) and tit, shag and booby from its discussion forums Framework Days. IT Saturday. 5.09.2015

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FILTER RULES Framework Days. IT Saturday. 5.09.2015 1. search by entry 2. search whole word 3. handle punctuation 4. handle l33t speak 5. remember about exceptions blue- footed booby!

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TEXT FILTERING ON IOS Framework Days. IT Saturday. 5.09.2015 words dictionary (boobs, b00bs, b00b5) whole word scan NSScanner, NSSet

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TEXT FILTERING ON IOS Framework Days. IT Saturday. 5.09.2015 phrases dictionary (b o o b s, b.o.o.b.s, b!o!o!bs) substring scan rangeOfString

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TEXT FILTERING ON IOS Framework Days. IT Saturday. 5.09.2015 words dictionary (boobs, b00bs, b00b5) whole word scan NSScanner, NSSet phrases dictionary (b o o b s, b.o.o.b.s, bo!obs) substring scan rangeOfString +

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HOW FAST IS IT? Framework Days. IT Saturday. 5.09.2015 time, seconds 0 0,1 0,2 0,3 0,4 user text, characters count 1000 5000 10000 20000 range scanner both dirty words dictionary contains 455 words

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LIVE FILTERING Framework Days. IT Saturday. 5.09.2015 use RAC and run ﬁlter every time user inputs character

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IMPROVE FILTERING • Keep dictionary up to date • Whitelist • Levenshtein distance • Soundex functions (where a word sounds like another) • Naive bayesian inference ﬁltering of phrases/terms Framework Days. IT Saturday. 5.09.2015

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POST-MODERATION Framework Days. IT Saturday. 5.09.2015 alive moderators solid community ﬂag abuse

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DIRTY WORDS • list of dirty words in different languages https://github.com/shutterstock/List-of-Dirty- Naughty-Obscene-and-Otherwise-Bad-Words • list of dirty words i’ve used https://gist.github.com/vixentael/ 5ce4168e3e94d9686405 Framework Days. IT Saturday. 5.09.2015

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LAST SLIDE @vixentael Framework Days. IT Saturday. 5.09.2015 iOS developer at Stanfy

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THANK YOU FOR WATCHING! Framework Days. IT Saturday. 5.09.2015