mirror of
https://github.com/idris-lang/Idris2.git
synced 2024-12-21 10:41:59 +03:00
40 lines
1.2 KiB
Idris
40 lines
1.2 KiB
Idris
module System.REPL
|
|
|
|
import System.File
|
|
|
|
%default covering
|
|
|
|
||| A basic read-eval-print loop, maintaining a state
|
|
|||
|
|
||| @ state the input state
|
|
||| @ prompt the prompt to show
|
|
||| @ onInput the function to run on reading input, returning a String to
|
|
||| output and a new state. Returns Nothing if the repl should exit
|
|
export
|
|
replWith : HasIO io =>
|
|
(state : a) -> (prompt : String) ->
|
|
(onInput : a -> String -> Maybe (String, a)) -> io ()
|
|
replWith acc prompt fn
|
|
= do eof <- fEOF stdin
|
|
if eof
|
|
then pure ()
|
|
else do putStr prompt
|
|
fflush stdout
|
|
x <- getLine
|
|
case fn acc x of
|
|
Just (out, acc') =>
|
|
do putStr out
|
|
replWith acc' prompt fn
|
|
Nothing => pure ()
|
|
|
|
||| A basic read-eval-print loop
|
|
|||
|
|
||| @ prompt the prompt to show
|
|
||| @ onInput the function to run on reading input, returning a String to
|
|
||| output
|
|
export
|
|
repl : HasIO io =>
|
|
(prompt : String) -> (onInput : String -> String) -> io ()
|
|
repl prompt fn
|
|
= replWith () prompt (\x, s => Just (fn s, ()))
|