| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Hackage.Security.Client.Formats
- data FormatUn
- data FormatGz
- data Format :: * -> * where
- data Formats :: * -> * -> * where
- data HasFormat :: * -> * -> * where
- hasFormatAbsurd :: HasFormat () f -> a
- hasFormatGet :: HasFormat fs f -> Format f
- formatsMap :: (forall f. Format f -> a -> b) -> Formats fs a -> Formats fs b
- formatsMember :: Format f -> Formats fs a -> Maybe (HasFormat fs f)
- formatsLookup :: HasFormat fs f -> Formats fs a -> a
Formats
Type level
Term level
data Format :: * -> * where Source
Format is a singleton type (reflection type to term level)
NOTE: In the future we might add further compression formats.
data Formats :: * -> * -> * where Source
Available formats
Rather than having a general list here, we enumerate all possibilities. This means we are very precise about what we expect, and we avoid any runtime errors about unexpect format definitions.
NOTE: If we add additional cases here (for dealing with additional formats)
all calls to error "inaccessible" need to be reevaluated.
Key membership
data HasFormat :: * -> * -> * where Source
HasFormat fs f is a proof that f is a key in fs.
See formatsMember and formatsLookup for typical usage.
Utility
hasFormatAbsurd :: HasFormat () f -> a Source
hasFormatGet :: HasFormat fs f -> Format f Source
Map-like operations
formatsMap :: (forall f. Format f -> a -> b) -> Formats fs a -> Formats fs b Source
formatsLookup :: HasFormat fs f -> Formats fs a -> a Source