Shard Detail

string_inflection v0.2.1

Yet another Crystal library for string inflection.

Install & Use

Add the following code to your project's shard.yml under:

dependencies to use in production
- OR -
development_dependencies to use in development

  github: mosop/string_inflection


Crystal String Inflection

Yet another Crystal library for string inflection.

Build Status


Add this to your application's shard.yml:

    github: mosop/string_inflection


require "string_inflection"

StringInflection.camel("foo bar")  # => "fooBar"
StringInflection.pascal("foo bar") # => "FooBar"
StringInflection.snake("foo bar")  # => "foo_bar"
StringInflection.kebab("foo bar")  # => "foo-bar"
StringInflection.plural("child")   # => "children"
StringInflection.singular("data")  # => "datum"

Or do you like shorthand? So you can use the Case module.

require "string_inflection/case"

Case.camel("foo bar")  # => "fooBar"
Case.pascal("foo bar") # => "FooBar"
Case.snake("foo bar")  # => "foo_bar"
Case.kebab("foo bar")  # => "foo-bar"
Case.plural("child")   # => "children"
Case.singular("data")  # => "datum"

Upper Case Replacement

With the :up option, singular / plural replaces a string with upper case letters.

StringInflection.plural("CHILD", up: true) # => "CHILDREN"
StringInflection.singular("DATA", up: true)  # => "DATUM"

Note: :up affects only a replaced substring.

StringInflection.plural("child", up: true) # => "childREN"
StringInflection.singular("data", up: true)  # => "datUM"


The special extension String#to makes things object-oriented.

require "string_inflection/string/to"

Then you can:

"foo bar".to.camel # => "fooBar"
"foo bar".to.pascal # => "FooBar"
"foo bar".to.snake  # => "foo_bar"
"foo bar".to.kebab  # => "foo-bar"
"child".to.plural   # => "children"
"data".to.singular  # => "datum"

Naming Methods


You can define inflection methods with your own names under your own namespaces.

Special Thanks

Automatically Generated Inflection Database (AGID)

The handy database by Kevin Atkinson and other authors is significantly useful to generate irregular singular/plural forms. You can see the license in README.


  • v0.2.0
    • (Breaking Change) StringInflection.define_inflector is separated into StringInflection.define_inflector and StringInflection.define_inflector_methods.
  • v0.1.7
    • Upper Case Replacement
  • v0.1.3
    • StringInflection.singular
  • v0.1.2
    • StringInflection.plural
  • v0.1.1
    • Case
    • String#to
    • StringInflection.define_inflector




  1. Fork it ( )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request


  • mosop - creator, maintainer