Data.Yaml.Config.Internal

Documentation

data Config

Type contains config section and path from root.

Constructors

Config [Key] Object

Instances

Eq Config

Show Config

NFData Config

newtype KeyError

This error can be raised if config has not target path.

Constructors

KeyError Key

Instances

Show KeyError

Typeable KeyError

Exception KeyError

type Key = Text

Config or field name

Work with files

load :: FilePath -> IO Config

Find file in filesystem and try to load it as YAML config. May fail with InvalidYaml if file not found.

>>> config <- load "example.yaml"

Explore config

keys :: Config -> [Key]

Show all first level config field's.

>>> keys config
["section1","section2"]

subconfig

Arguments

:: Failure KeyError m

=> Key

Subconfig name

-> Config

(Sub)Config for find

-> m Config

Founded Subconfig

Get subconfig by name. May fail with KeyError if target key doesn't exist at current level.

>>> :set -XOverloadedStrings
>>> sub <- subconfig "section1" config

lookup

Arguments

:: (Failure KeyError m, FromJSON a)

=> Key

Field name

-> Config

Config for find

-> m a

Field value

Get value for given key. May fail with KeyError if key doesn't exist.

>>> keys sub
["field1","field2"]
>>> putStrLn =<< lookup "field1" sub
value1

lookupDefault

Arguments

:: FromJSON a

=> Key

Field name

-> a

Default value

-> Config

Config for find

-> a

Founded or default value

Find value in config and return it or return default value.

>>> lookupDefault "field3" "def" sub
"def"

fullpath :: Config -> Key -> Key

Show full path from the root to target key. Levels are separated by dots.

>>> fullpath sub "field1"
"section1.field1"