The urlpath package

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Simple URL DSL for Haskell.

This library tries to make it easier for people to write Url strings, structurally. Packages like Yesod Routes do a wonderful job at implementing string-free routing and references, but sometimes we have to compromise. This tries to make that compromise less painful.

Use bare combinators to render your strings (kinda useless):

  expandRelative $ "foo.php" <?> ("key1","bar") <&> ("key2","baz")

  ↪ "foo.php?key1=bar&key2=baz"

... or use the MonadReader instance for a configurable host:

  let path = runAbsoluteUrl $ url $ "foo.php" <?> ("key1","bar") <&> ("key2","baz")
  path ""

  ↪ ""

url puts the UrlString in a MonadReader that we can use for applying our host. We use different monads for different deployment schemes (currently we have 3 - RelativeUrl, GroundedUrl, and AbsoluteUrl), which we can integrate in different libraries, like Lucid:

  (runAbsoluteUrl $ renderTextT $ do
      foo <- lift $ url $ "foo" <?> ("bar","baz")
      script_ [src_ foo] "" )
  ) ""

  ↪ "<script src=\"\"></script>"

... and in Scotty ...

  main :: IO ()
  main = scottyT 3000

      rootConf = flip runAbsoluteT ""

      run :: ( MonadIO m
             , MonadReader T.Text m
             , Url T.Text m ) =>
             ScottyT LT.Text m ()
      run = get "/" $ do
        path <- lift $ url $ "foo" <?> ("bar","baz")
        text $ LT.fromStrict path

  λ> curl localhost:3000/
  ↪ ""

Note that in the scotty example, we don't use one of our deployment schemes - this is because the scottyT function expects it's underlying monad to be an instance of MonadIO, which we can only instantiate in our monad transformers.

Please take mind - the string type underlying the Url rendering is generalized to Data.String.IsString for convenient use with -XOverloadedStrings. However, due to that generality, we need to specify the monomorphic type (like Data.Text.Text above).


Versions0.0.1, 0.0.2, 0.0.3, 0.0.4, 0.0.5, 0.0.6, 0.1, 0.1,, 0.2, 1.0.0, 1.1.0, 2.0.0, 2.1.0, 3.0.0, 3.1.0, 3.1.1, 3.2.0, 3.2.1,, 3.3.0, 4.0.0,, 4.1.0, 4.2.0, 5.0.0,
Change logNone available
Dependenciesbase (==4.*), mtl, text, transformers [details]
AuthorAthan Clark <>
MaintainerAthan Clark <>
Source repositoryhead: git clone
UploadedThu Dec 18 18:54:24 UTC 2014 by athanclark




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