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Countable Inflections

License MIT Hackage Stackage LTS

This library implements pluralization and singularization in a similar way to the rails inflectors

It uses regexes to define the non-standard transformations and therefore doesn't provide much safety. If you need to provide the same pluralization and singularization which rails does out of the box, this will work the same. If you want more you should be using inflections-hs which uses megaparsec to give you more guarantees


λ: pluralize "person"

λ: singularize "branches"

These can also be given custom inflection matchers

λ: :t singularizeWith
[Inflection] -> Text -> Text

There are 3 different types of transformations:


Takes a PCRE regex and a replacement string.

λ: :t makeMatchMapping
[(RegexPattern, RegexReplace)] -> [Inflection]

λ: let mapping = makeMatchMapping [("(octop)us", "\\1i")]
λ: pluralizeWith mapping "octopus"


From singular to plural with no greater pattern.

λ: :t makeIrregularMapping
[(Singular, Plural)] -> [Inflection]

λ: let mapping = makeIrregularMapping [("zombie","zombies")]
λ: pluralizeWith mapping "zombie"


Doesn't have a mapping, word stays the same) so it has the type:

[Text] -> [Inflection]


In general you can input a number and singularize or pluralize based on the count, for example:

setReport = do
  sets <- getSets
  n <- length sets
  print $ show n ++ " " ++ inflect "sets" n

This way it'll list as "1 set" or "5 sets" based on the input.


MIT - see the LICENSE file.