Web.Slug

Type-safe slug implementation for Yesod ecosystem.

Documentation

data Slug

Slug. Textual value inside is always guaranteed to have the following qualities:

• it's not empty;
• it consists only of alpha-numeric groups of characters (words) separated by '-' dashes in such a way that entire slug cannot start or end in a dash and also two dashes in a row cannot be found;
• every character with defined notion of case is lower-cased.

Slugs are good for semantic URLs and also can be used as identifier of a sort in some cases.

Instances

Eq Slug

Show Slug

ToJSON Slug

FromJSON Slug

PathPiece Slug

PersistFieldSql Slug

PersistField Slug

mkSlug :: MonadThrow m => Text -> m Slug

Create Slug from Text, all necessary transformations are applied. Argument of this function can be title of an article or something like that.

Note that result is inside MonadThrow, that means you can just get it in Maybe, in more complex contexts it will throw SlugException.

This function also have a useful property:

mkSlug = mkSlug >=> mkSlug . unSlug

unSlug :: Slug -> Text

Get textual representation of Slug.

data SlugException

This exception is thrown by mkSlug when its input cannot be converted into proper Slug.

Constructors

InvalidInput Text

Instances

Show SlugException

Exception SlugException