{"id":26295816,"url":"https://github.com/aiya000/hs-character-cases","last_synced_at":"2025-05-09T00:46:42.938Z","repository":{"id":62435695,"uuid":"248735062","full_name":"aiya000/hs-character-cases","owner":"aiya000","description":"A Haskell library for subspecies types of Char, and naming cases.","archived":false,"fork":false,"pushed_at":"2021-03-18T13:39:58.000Z","size":24,"stargazers_count":8,"open_issues_count":2,"forks_count":0,"subscribers_count":2,"default_branch":"master","last_synced_at":"2025-05-09T00:46:33.912Z","etag":null,"topics":["haskelll","parser-combinators","quasiquoter","template-haskell"],"latest_commit_sha":null,"homepage":"https://hackage.haskell.org/package/character-cases","language":"Haskell","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/aiya000.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2020-03-20T11:06:31.000Z","updated_at":"2021-01-25T06:16:25.000Z","dependencies_parsed_at":"2022-11-01T21:33:44.337Z","dependency_job_id":null,"html_url":"https://github.com/aiya000/hs-character-cases","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/aiya000%2Fhs-character-cases","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/aiya000%2Fhs-character-cases/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/aiya000%2Fhs-character-cases/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/aiya000%2Fhs-character-cases/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/aiya000","download_url":"https://codeload.github.com/aiya000/hs-character-cases/tar.gz/refs/heads/master","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":253171216,"owners_count":21865282,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["haskelll","parser-combinators","quasiquoter","template-haskell"],"created_at":"2025-03-15T04:15:14.948Z","updated_at":"2025-05-09T00:46:42.896Z","avatar_url":"https://github.com/aiya000.png","language":"Haskell","funding_links":[],"categories":[],"sub_categories":[],"readme":"# :diamond_shape_with_a_dot_inside: character-cases :diamond_shape_with_a_dot_inside:\n\n[![](https://img.shields.io/hackage/v/character-cases)](https://hackage.haskell.org/package/character-cases)\n\nA Haskell library for subspecies types of Char, and naming cases.\n\n- Naming cases (String like)\n\n```haskell\n-- | [A-Z][a-zA-Z0-9]*\ndata Pascal = Pascal UpperChar [AlphaNumChar]\n  deriving (Show, Eq)\n\n-- | [a-z][a-zA-Z0-9]*\ndata Camel = Camel AlphaChar [AlphaNumChar]\n  deriving (Eq)\n\n-- | [a-zA-Z_][a-zA-Z0-9_]*\ndata Snake = Snake SnakeHeadChar [SnakeChar]\n  deriving (Show, Eq)\n\n-- | [A-Z_][A-Z0-9_]*\ndata UpperSnake = UpperSnake UpperSnakeHeadChar [UpperSnakeChar]\n  deriving (Show, Eq)\n\n-- | [a-z]+\ndata LowerString = LowerString LowerChar [LowerChar]\n  deriving (Show, Eq)\n\n-- | .+\ndata NonEmpty = NonEmpty Char String\n  deriving (Show, Eq)\n```\n\n- Subspecies types (Char like)\n\n```haskell\n-- | [A-Z]\ndata UpperChar = ...\n  deriving (Show, Eq, Ord)\n\n-- | [a-z]\ndata LowerChar = ...\n  deriving (Show, Eq, Ord)\n\n-- | [0-9]\ndata DigitChar = ...\n  deriving (Show, Eq, Ord)\n\n-- | [A-Za-z]\ndata AlphaChar = ...\n  deriving (Show, Eq, Ord)\n\n-- | [A-Za-z0-9]\ndata AlphaNumChar = ...\n  deriving (Show, Eq, Ord)\n```\n\n## Why we use this?\n\n**Make impossible things to impossible** to strict `data` driven programming.\n\nFor example, in the first place,\n\n- `List.NonEmpty a` wont be the empty list `[]`\n\nalso\n\n- `Pascal` wont be other than `[A-Z][a-zA-Z0-9]*`\n- `Camel` wont be other than `[a-z][a-zA-Z0-9]*`\n- ...\n\nThese are useful in\n\n- Abstract Syntax Tree (Identifiers)\n- ...\n\n**Make impossible things to impossible.**\n\n## Usage\n\n- [character-cases - Hackage](https://hackage.haskell.org/package/character-cases)\n\n- [Data.Char.Cases](https://github.com/aiya000/hs-character-cases/blob/master/src/Data/Char/Cases.hs)\n- [Data.String.Cases](https://github.com/aiya000/hs-character-cases/blob/master/src/Data/String/Cases.hs)\n\n### `QuasiQuoter`s\n\nThat ADT can be used directly, but `QuasiQuoter`s is more useful.\n\n- Naming cases\n\n```haskell\n\u003e\u003e\u003e [pascalQ|Pascal|]\nPascal P [AlphaNumAlpha (AlphaLower A_),AlphaNumAlpha (AlphaLower S_),AlphaNumAlpha (AlphaLower C_),AlphaNumAlpha (AlphaLower A_),AlphaNumAlpha (AlphaLower L_)]\n\n\u003e\u003e\u003e [nonEmptyQ|x|]\nNonEmpty 'x' \"\"\n\u003e\u003e\u003e [nonEmptyQ|foo|]\nNonEmpty 'f' \"oo\"\n\u003e\u003e\u003e [nonEmptyQ|Bar|]\nNonEmpty 'B' \"ar\"\n\n\u003e\u003e\u003e [camelQ|camel|]\n\"camel\"\n\u003e\u003e\u003e [camelQ|Pascal|]\n\"Pascal\"\n\n\u003e\u003e\u003e [snakeQ|foo_bar|]\nSnake (SnakeHeadAlpha (AlphaLower F_)) [SnakeAlphaNum (AlphaNumAlpha (AlphaLower O_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower O_)),SnakeUnderscore,SnakeAlphaNum (AlphaNumAlpha (AlphaLower B_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower A_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower R_))]\n\u003e\u003e\u003e [snakeQ|__constructor|]\nSnake SnakeHeadUnderscore [SnakeUnderscore,SnakeAlphaNum (AlphaNumAlpha (AlphaLower C_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower O_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower N_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower S_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower T_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower R_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower U_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower C_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower T_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower O_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower R_))]\n\u003e\u003e\u003e [snakeQ|FOO_MEE_9|]\nSnake (SnakeHeadAlpha (AlphaUpper F)) [SnakeAlphaNum (AlphaNumAlpha (AlphaUpper O)),SnakeAlphaNum (AlphaNumAlpha (AlphaUpper O)),SnakeUnderscore,SnakeAlphaNum (AlphaNumAlpha (AlphaUpper M)),SnakeAlphaNum (AlphaNumAlpha (AlphaUpper E)),SnakeAlphaNum (AlphaNumAlpha (AlphaUpper E)),SnakeUnderscore,SnakeAlphaNum (AlphaNumDigit D9)]\n\n\u003e\u003e\u003e [lowerStringQ|imavimmer|]\nLowerString I_ [M_,A_,V_,I_,M_,M_,E_,R_]\n```\n\n- Characters\n\n```haskell\n\u003e\u003e\u003e [upperCharQ|X|]\nX\n\n\u003e\u003e\u003e [lowerCharQ|x|]\nX_\n\n\u003e\u003e\u003e [digitCharQ|0|]\nD0\n\n\u003e\u003e\u003e [alphaNumCharQ|X|]\nAlphaNumAlpha (AlphaUpper X)\n\n\u003e\u003e\u003e [alphaNumCharQ|x|]\nAlphaNumAlpha (AlphaLower X_)\n\n\u003e\u003e\u003e [alphaNumCharQ|0|]\nAlphaNumDigit D0\n\n\u003e\u003e\u003e [snakeCharQ|_|]\nSnakeUnderscore\n```\n\nWrong cases will be rejected on **the compile time**!\n\n```haskell\n\u003e\u003e\u003e [upperCharQ|x|]\nerror:\n    • ''x'' is not an UpperChar.\n    • In the quasi-quotation: [upperCharQ|x|]\n\n\u003e\u003e\u003e [lowerCharQ|X|]\nerror:\n    • ''X'' is not a LowerChar.\n    • In the quasi-quotation: [lowerCharQ|X|]\n\n\u003e\u003e\u003e [alphaNumCharQ|one or more characters|]\nerror:\n    • alphaNumCharQ required a Char, but a String is specified: one or more characters\n    • In the quasi-quotation: [alphaNumCharQ|one or more characters|]\n```\n\n```haskell\n\u003e\u003e\u003e [pascalQ|camel|]\nerror:\n    • ''c'' is not an UpperChar.\n    • In the quasi-quotation: [pascalQ|camel|]\n\n\u003e\u003e\u003e [nonEmptyQ||]\nerror:\n    • nonEmptyQ required a non empty string, but the empty string is specified.\n    • In the quasi-quotation: [nonEmptyQ||]\n\n\u003e\u003e\u003e [camelQ|snake_case|]\nerror:\n    • ''_'' is not an AlphaNumChar.\n    • In the quasi-quotation: [camelQ|snake_case|]\n\n\u003e\u003e\u003e [lowerStringQ|Upper|]\nerror:\n    • ''U'' is not a LowerChar.\n    • In the quasi-quotation: [lowerStringQ|Upper|]\n```\n\nPlease also see doctests of modules.\n\n- [Data.Char.Cases](https://github.com/aiya000/hs-character-cases/blob/master/src/Data/Char/Cases.hs)\n- [Data.String.Cases](https://github.com/aiya000/hs-character-cases/blob/master/src/Data/String/Cases.hs)\n\n### Parser combinators\n\nAnd we can use it as parser combinators.\n\nPlease see modules and documents.\n\n- [character-cases - Hackage](https://hackage.haskell.org/package/character-cases)\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Faiya000%2Fhs-character-cases","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Faiya000%2Fhs-character-cases","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Faiya000%2Fhs-character-cases/lists"}