{-# LANGUAGE OverloadedStrings #-} -- -- | -- Maintainer: Andrew Cowie -- Stability: Experimental -- -- /Background/ -- -- We had a need for identifiers that could be used by humans. -- -- The requirement to be able to say these over the phone complicates matters. -- Most people have approached this problem by using a phonetic alphabet. The -- trouble comes when you hear people saying stuff like \"A as in ... uh, -- Apple?\" (should be Alpha, of course) and \"U as in ... um, what's a word -- that starts with U?\" It gets worse. Ever been to a GPG keysigning? Listen -- to people attempt to read out the digits of their key fingerprints. ...C 3 E -- D 0 0 0 0 0 0 0 2 B D B D... \"Did you say \'C\' or \'D\'?\" and \"how -- many zeros was that?\" Brutal. -- -- So what we need is a symbol set where each digit is unambigious and doesn't -- collide with the phonetics of another symbol. This package provides -- 'English16', a set of 16 letters and numbers that, when spoken in /English/, -- have unique pronounciation and have been very successful in verbal -- communications over noisy links. -- -- Ironically, however, when used in written applications the English16 set is -- a bit restrictive. When /looking/ at them they don't have much variety (it -- turned out they're very blocky—so much so you have to squint). If the -- application is transcription or identification visually then the criteria is -- shapes that are distinct, rather than their sound. For these uses we provide -- 'Latin25', a set of 25 symbols useful for identifiers in automated systems -- that nevertheless have to be operated or debugged by humans. -- -- Finally, also included is code to work in base 62, which is simply -- @[\'0\'@-@\'9\'@, @\'A\'@-@\'Z\'@, and @\'a\'@-@\'z\']@. These are -- frequently used to express short codes in URL redirectors; you may find them -- a more useful encoding for expressing numbers than base 16 hexidecimal. -- module Data.Locator ( -- * English16: locators humans can exchange -- | This was somewhat inspired by the record locators used by the civilian -- air travel industry, but with the restriction that the symbol set is -- carefully chosen (aviation locators do heroic things like excluding -- \'I\' but not much else) and, in the case of Locator16a, to not repeat -- symbols. They're not a reversable encoding, but assuming you're just -- generating identifiers and storing them somewhere, they're quite handy. -- -- @TODO@ /link to paper with pronunciation study when published./ -- Locator(..) , English16(..) , fromEnglish16 , toEnglish16 , toEnglish16a , hashStringToEnglish16a -- * Latin25: a visually distinct character set -- An althernate character set chosen for visual distinctiveness (rather -- than the aural distinctiveness goal of "English16"). , Latin25(..) , fromLatin25 , toLatin25 , hashStringToLatin25 -- * Base62: binary without punctuation , toBase62 , fromBase62 , padWithZeros , hashStringToBase62 -- * Deprecated functions , fromLocator16 , toLocator16 , toLocator16a , hashStringToLocator16a ) where import Data.Locator.Common import Data.Locator.Hashes import Data.Locator.English16 import Data.Locator.Latin25