Natural sorting: Difference between revisions

import Data.List

import Data.Char

import Data.String.Utils

import Data.List.Utils

import Data.Function (on)

printOutput = do

putStrLn "# Ignoring leading spaces \n"

printBlockOfMessages sample1Rule ignoringStartEndSpaces

putStrLn "\n # Ignoring multiple adjacent spaces (m.a.s) \n"

printBlockOfMessages sample2Rule ignoringMultipleAdjacentSpaces

putStrLn "\n # Equivalent whitespace characters \n"

printBlockOfMessages sample3Rule ignoringMultipleAdjacentSpaces

putStrLn "\n # Case Indepenent sorts \n"

printBlockOfMessages sample4Rule caseIndependent

putStrLn "\n # Numeric fields as numerics \n"

printBlockOfMessages sample5Rule numericFieldsAsNumbers

putStrLn "\n # Title sorts \n"

printBlockOfMessages sample6Rule removeLeadCommonWords

printMessage message content = do

putStrLn message

mapM_ print content

printBlockOfMessages list function = do

printMessage "Text strings:" list

printMessage "Normally sorted:" (sort list)

printMessage "Naturally sorted:" (sortListWith list function)

-- samples

sample1Rule = ["ignore leading spaces: 2-2", " ignore leading spaces: 2-1", " ignore leading spaces: 2+0", " ignore leading spaces: 2+1"]

sample2Rule = ["ignore m.a.s spaces: 2-2", "ignore m.a.s spaces: 2-1", "ignore m.a.s spaces: 2+0", "ignore m.a.s spaces: 2+1"]

sample3Rule = ["Equiv. spaces: 3-3", "Equiv.\rspaces: 3-2", "Equiv.\x0cspaces: 3-1", "Equiv.\x0bspaces: 3+0", "Equiv.\nspaces: 3+1", "Equiv.\tspaces: 3+2"]

sample4Rule = ["cASE INDEPENENT: 3-2", "caSE INDEPENENT: 3-1", "casE INDEPENENT: 3+0", "case INDEPENENT: 3+1"]

sample5Rule = ["foo100bar99baz0.txt", "foo100bar10baz0.txt", "foo1000bar99baz10.txt", "foo1000bar99baz9.txt"]

sample6Rule = ["The Wind in the Willows", "The 40th step more", "The 39 steps", "Wanda"]

-- function to execute all sorts

sortListWith l f = sort $ f l

-- 1. Ignore leading, trailing and multiple adjacent spaces

-- Ignoring leading spaces

-- receive a String and remove all spaces from the start and end of that String, a String is considered an List os Char

-- ex: " a string " = "a string"

ignoringStartEndSpaces :: [String] -> [String]

ignoringStartEndSpaces = map strip

-- Ignoring multiple adjacent spaces and Equivalent whitespace characters

ignoringMultipleAdjacentSpaces :: [String] -> [String]

ignoringMultipleAdjacentSpaces = map (unwords . words)

-- 2. Equivalent whitespace characters

-- 3. Case independent sort

-- lower case of an entire String

-- ex "SomeCAse" = "somecase"

caseIndependent :: [String] -> [String]

caseIndependent = map (map toLower)

-- 4. Numeric fields as numerics (deals with up to 20 digits)

numericFieldsAsNumbers :: [String] -> [[Int]]

numericFieldsAsNumbers = map findOnlyNumerics

findOnlyNumerics :: String -> [Int]

findOnlyNumerics s = convertDigitAsStringToInt $ makeListOfDigitsAsString $ extractDigitsAsString s

extractDigitsAsString :: String -> [String]

extractDigitsAsString s = map (filter isNumber) $ groupBy ((==) `on` isNumber ) s

makeListOfDigitsAsString :: [String] -> [String]

makeListOfDigitsAsString l = tail $ nub l

convertDigitAsStringToInt :: [String] -> [Int]

convertDigitAsStringToInt = map (joiner . map digitToInt)

-- join a list of numbers into a single number

-- ex [4,2] = 42

joiner :: [Int] -> Int

joiner = read . concatMap show

-- 5. Title sort

removeLeadCommonWords l = map removeLeadCommonWord $ splitList l

splitList = map words

removeLeadCommonWord a = unwords $ if f a commonWords then tail a else a

where f l1 = elem (map toLower (head l1))

commonWords = ["the","a","an","of"]

{{out}}

<pre style="height: 80ex; overflow: scroll">

# Ignoring leading spaces

Text strings:

"ignore leading spaces: 2-2"

" ignore leading spaces: 2-1"

" ignore leading spaces: 2+0"

" ignore leading spaces: 2+1"

Normally sorted:

" ignore leading spaces: 2+1"

" ignore leading spaces: 2+0"

" ignore leading spaces: 2-1"

"ignore leading spaces: 2-2"

Naturally sorted:

"ignore leading spaces: 2+0"

"ignore leading spaces: 2+1"

"ignore leading spaces: 2-1"

"ignore leading spaces: 2-2"

# Ignoring multiple adjacent spaces (m.a.s)

Text strings:

"ignore m.a.s spaces: 2-2"

"ignore m.a.s spaces: 2-1"

"ignore m.a.s spaces: 2+0"

"ignore m.a.s spaces: 2+1"

Normally sorted:

"ignore m.a.s spaces: 2+1"

"ignore m.a.s spaces: 2+0"

"ignore m.a.s spaces: 2-1"

"ignore m.a.s spaces: 2-2"

Naturally sorted:

"ignore m.a.s spaces: 2+0"

"ignore m.a.s spaces: 2+1"

"ignore m.a.s spaces: 2-1"

"ignore m.a.s spaces: 2-2"

# Equivalent whitespace characters

Text strings:

"Equiv. spaces: 3-3"

"Equiv.\rspaces: 3-2"

"Equiv.\fspaces: 3-1"

"Equiv.\vspaces: 3+0"

"Equiv.\nspaces: 3+1"

"Equiv.\tspaces: 3+2"

Normally sorted:

"Equiv.\tspaces: 3+2"

"Equiv.\nspaces: 3+1"

"Equiv.\vspaces: 3+0"

"Equiv.\fspaces: 3-1"

"Equiv.\rspaces: 3-2"

"Equiv. spaces: 3-3"

Naturally sorted:

"Equiv. spaces: 3+0"

"Equiv. spaces: 3+1"

"Equiv. spaces: 3+2"

"Equiv. spaces: 3-1"

"Equiv. spaces: 3-2"

"Equiv. spaces: 3-3"

# Case Indepenent sorts

Text strings:

"cASE INDEPENENT: 3-2"

"caSE INDEPENENT: 3-1"

"casE INDEPENENT: 3+0"

"case INDEPENENT: 3+1"

Normally sorted:

"cASE INDEPENENT: 3-2"

"caSE INDEPENENT: 3-1"

"casE INDEPENENT: 3+0"

"case INDEPENENT: 3+1"

Naturally sorted:

"case indepenent: 3+0"

"case indepenent: 3+1"

"case indepenent: 3-1"

"case indepenent: 3-2"

# Numeric fields as numerics

Text strings:

"foo100bar99baz0.txt"

"foo100bar10baz0.txt"

"foo1000bar99baz10.txt"

"foo1000bar99baz9.txt"

Normally sorted:

"foo1000bar99baz10.txt"

"foo1000bar99baz9.txt"

"foo100bar10baz0.txt"

"foo100bar99baz0.txt"

Naturally sorted:

[100,10,0]

[100,99,0]

[1000,99,9]

[1000,99,10]

# Title sorts

Text strings:

"The Wind in the Willows"

"The 40th step more"

"The 39 steps"

"Wanda"

Normally sorted:

"The 39 steps"

"The 40th step more"

"The Wind in the Willows"

"Wanda"

Naturally sorted:

"39 steps"

"40th step more"

"Wanda"

"Wind in the Willows"

</pre>