Data.Text.Edits

This module provides a showDistance function showing the differences between 2 pieces of text using the Levenshtein distance. That distance is defined as the minimum number of edits: insertions, deletions, substitutions to go from one text to another.

Several options are available to customize this processing: - split size: texts are broken into new lines first. Then if the texts are too large there are split into smaller pieces in order to compute their difference. This is done in order to reduce the size of the edit matrix which is used to compute all the edit costs the default is 200

• separators: opening and closing pieces of text (brackets by default) used to highlight a difference
• shorten size: there is the possibly to display mostly the differences with a bit of context around if the input text is too large. The text gets elided around separators if it gets greater than the shorten size (the default is 20)
• shorten text: the text to use when eliding characters in the original text (the default is "...")
• display edit operations: edit operations, insertdeletesubstitute/keep can be annotated if necessary

Here are some examples:

import Data.Text.Edits

-- "between the e and the n the letter i was added"
showDistance "kitten" "kittein" === "kitte[+i]n"

-- "at the end of the text 3 letters have been deleted"
showDistance "kitten" "kit" === "kit[-t-e-n]"

-- "between the t and the n 2 letters have been modified"
showDistance "kitten" "kitsin" === "kit[~ts~ei]"

Documentation

newtype SplitSize

Size to use when splitting a large piece of text

Constructors

SplitSize Int

Instances

Show SplitSize

Defined in Data.Text.Edits

Methods

showsPrec :: Int -> SplitSize -> ShowS

show :: SplitSize -> String

showList :: [SplitSize] -> ShowS

Eq SplitSize

Defined in Data.Text.Edits

Methods

(==) :: SplitSize -> SplitSize -> Bool

(/=) :: SplitSize -> SplitSize -> Bool

data ShortenOptions

Size used to decide if a piece of text needs to be shortened

Constructors

ShortenOptions

Fields

• _shortenSize :: Int
• _shortenText :: Text

Instances

Show ShortenOptions

Defined in Data.Text.Shorten

Methods

showsPrec :: Int -> ShortenOptions -> ShowS

show :: ShortenOptions -> String

showList :: [ShortenOptions] -> ShowS

Eq ShortenOptions

Defined in Data.Text.Shorten

Methods

(==) :: ShortenOptions -> ShortenOptions -> Bool

(/=) :: ShortenOptions -> ShortenOptions -> Bool

data Separators

Separators are used to highlight a difference between 2 pieces of text for example

Constructors

Separators

Fields

• startSeparator :: Text
• endSeparator :: Text

Instances

Show Separators

Defined in Data.Text.Difference

Methods

showsPrec :: Int -> Separators -> ShowS

show :: Separators -> String

showList :: [Separators] -> ShowS

Eq Separators

Defined in Data.Text.Difference

Methods

(==) :: Separators -> Separators -> Bool

(/=) :: Separators -> Separators -> Bool

data DisplayOptions

Options to use for displaying differences

Constructors

DisplayOptions

Fields

• _separators :: Separators
• _shortenOptions :: ShortenOptions
• _displayEditOperation :: EditOperation Char -> Text

data EditOperation a

Atomic operation required to edit a piece of text at a given position in the EditMatrix

Constructors

Insert a

Delete a

Substitute a a

Keep a

Instances

Show a => Show (EditOperation a)

Defined in Data.Text.EditOperation

Methods

showsPrec :: Int -> EditOperation a -> ShowS

show :: EditOperation a -> String

showList :: [EditOperation a] -> ShowS

Eq a => Eq (EditOperation a)

Defined in Data.Text.EditOperation

Methods

(==) :: EditOperation a -> EditOperation a -> Bool

(/=) :: EditOperation a -> EditOperation a -> Bool

data Color

Available ASCII colors

Constructors

Black

Red

Green

Yellow

Blue

Magenta

Cyan

White

Instances

Show Color

Defined in Data.Text.Color

Methods

showsPrec :: Int -> Color -> ShowS

show :: Color -> String

showList :: [Color] -> ShowS

Eq Color

Defined in Data.Text.Color

Methods

(==) :: Color -> Color -> Bool

(/=) :: Color -> Color -> Bool

colorAs :: Color -> Text -> Text

Surround a piece of text with ASCII control characters to color it

showDistance :: Text -> Text -> Text

Show the distance between 2 pieces of text

showDistanceColored :: Text -> Text -> Text

Show the distance between 2 pieces of text with colors instead of symbols

showDistanceWith :: SplitSize -> DisplayOptions -> Text -> Text -> Text

Show the distance between 2 pieces of text and specify splitting / display options

levenshteinOperations :: Text -> Text -> [EditOperation Char]

Return the list of operations necessary to go from one piece of text to another using the Levenshtein distance

defaultDisplayOptions :: DisplayOptions

Default display options

defaultDisplayEditOperations :: EditOperation Char -> Text

Display an edit operation by prepending a symbol showing which operation is used

coloredDisplayEditOperation :: EditOperation Char -> Text

Display an edit operation using ascii colors: green = added, red = removed, blue = substituted

defaultSplitSize :: SplitSize

Default split size

parensSeparators :: Separators

Make parens separators

bracketsSeparators :: Separators

Make brackets separators

makeCharSeparators :: Char -> Char -> Separators

Make separators with simple Chars