Quick and easy configuration files in the INI format for Haskell.

Format rules and recommendations:

• foo: bar or foo=bar are allowed.
• The : syntax is space-sensitive.
• Keys are case-sensitive.
• Lower-case is recommended.
• Values can be empty.
• Keys cannot contain :, =, [, or ].
• Comments must start at the beginning of the line with ; or #.

An example configuration file:

# Some comment.
[SERVER]
port=6667
hostname=localhost
[AUTH]
user=hello
pass=world
# Salt can be an empty string.
salt=

Parsing example:

> parseIni "[SERVER]\nport: 6667\nhostname: localhost"
Right (Ini {unIni = fromList [("SERVER",fromList [("hostname","localhost")
                                                 ,("port","6667")])]})

Extracting values:

> parseIni "[SERVER]\nport: 6667\nhostname: localhost" >>=
  lookupValue "SERVER" "hostname"
Right "localhost"

Parsing:

> parseIni "[SERVER]\nport: 6667\nhostname: localhost" >>=
  readValue "SERVER" "port" decimal
Right 6667

Import Data.Text.Read to use decimal.

ini-qq provides a quasiquoter for INI.