ghci

The Glasgow Haskell Compiler's interactive environment. More information: https://downloads.haskell.org/ghc/latest/docs/html/users_guide/ghci.html.

Start a REPL (interactive shell):

ghci

Start a REPL and load the specified Haskell source file:

ghci {{source_file.hs}}

Start a REPL and enable a language option:

ghci -X{{language_option}}

Start a REPL and enable some level of compiler warnings (e.g. all or compact):

ghci -W{{warning_level}}

Start a REPL with a colon-separated list of directories for finding source files:

ghci -i{{path/to/directory1:path/to/directory2:...}}