System.Console.CmdTheLine.Term

Evaluating Terms

Simple command line programs

eval :: [String] -> (Term a, TermInfo) -> IO a

eval args ( term, termInfo ) allows the user to pass args directly to the evaluation mechanism. This is useful if some kind of pre-processing is required. If you do not need to pre-process command line arguments, use one of exec or run. On failure the program exits.

exec :: (Term a, TermInfo) -> IO a

exec ( term, termInfo ) executes a command line program, directly grabbing the command line arguments from the environment and returning the result upon successful evaluation of term. On failure the program exits.

run :: (Term (IO a), TermInfo) -> IO a

run ( term, termInfo ) runs a term containing an IO action, performs the action, and returns the result on success. On failure the program exits.

Multi-command command line programs

evalChoice :: [String] -> (Term a, TermInfo) -> [(Term a, TermInfo)] -> IO a

evalChoice args mainTerm choices is analogous to eval, but for programs that provide a choice of commands.

execChoice :: (Term a, TermInfo) -> [(Term a, TermInfo)] -> IO a

Analogous to exec, but for programs that provide a choice of commands.

runChoice :: (Term (IO a), TermInfo) -> [(Term (IO a), TermInfo)] -> IO a

Analogous to run, but for programs that provide a choice of commands.