Maps strings onto an integer output range. Can be used to calculate an ordering parameter for a list of items (based on e.g. their name), while attempting to minimize the chances of collisions when new items are inserted.
go get github.com/rubenv/utf8mapper
Import into your application with:
import "github.com/rubenv/utf8mapper"func MapString(str string, lower, upper int32) (int32, error)Maps a string to an index between lower and upper (inclusive), such that the chance of collisions is minimal.
Distribution of characters:
- 0000 - 00FF: 50% (ASCII + some Latin1)
- 0100 - 01FF: 10% (Latin extended)
- 0200 - 1FFF: 10% (Remaining basic languages)
- 2000 - FFFF: 10% (Remainder of Plane 0)
- 10000 - 1FFFF: 5% (Plane 1)
- 20000 - 2FFFF: 5% (Plane 2)
- 30000 - 10FFFF: 10% (Planes 3 - 16)
When mapping from 0 to math.MaxInt32, this gives us:
- 0000 - 00FF: 256 code points, 4194304 slots per code point
- 0100 - 01FF: 256 code points, 838861 slots per code point
- 0200 - 1FFF: 7680 code points, 27962 slots per code point
- 2000 - FFFF: 57344 code points, 3745 slots per code point
- 10000 - 1FFFF: 65536 code points, 1638 slots per code point
- 20000 - 2FFFF: 65536 code points, 1638 slots per code point
- 30000 - 10FFFF: 917504 code points, 234 slots per code point
(The MIT License)
Copyright (C) 2014 by Ruben Vermeersch <ruben@rocketeer.be>
Permission is hereby granted, free of charge, to any person obtaining a copy
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