sdiehl / repline Goto Github PK

In line 89 of System.Console.Repline, not enough arguments have been applied to evalRepl:

main = evalRepl (pure ">>> ") cmd options (Just ':') (Word completer) ini

This is standard behavior for internet chats and highly convenient

$ cabal haddock -w ghc-8.4.4
...
src/System/Console/Repline.hs:247:3: error:
    parse error on input ‘-- | banner function’
    |
247 |   -- | banner function
    |   ^^^^^^^^^^^^^^^^^^^^

@basile-henry mentioned this in https://github.com/dhall-lang/dhall-haskell/pull/1867/files#r441794458.

I'd recommend checking haddock-compatibility in CI BTW.

I was trying to get Repline working in a project of mine and wasn't able to get command options to work. So I made a test stack project where I copy pasted in the exact Simple example code and still the command options did not work:

Welcome!
>>> 
kirk   spock  mccoy
>>> kirk 
"kirk "
>>> spam
"spam"
>>> :say Hello Haskell
":say Hello Haskell"
>>> :help arg1 arg2 arg3
":help arg1 arg2 arg3"

I'm using thelts-14.13 resolver. Here is a link to my sample project:
https://github.com/ssbothwell/replinetest

At the moment the master branch has a cabal file, which states version 0.2.0.0
but there is a version 0.2.1.0 on hackage.

I am confused? Where is the git repo for the code of version 0.2.1.0?

Right now, repline-0.2.2.0 imports System.Console.Haskeline.MonadException, which only exists in haskeline < 0.8.0.0

Thanks!

vanessa@vanessa-desktop ~/git-builds/junk/repline-0.2.2.0 🌸 cabal build --constraint='haskeline >= 0.8.0.0'
Resolving dependencies...
Build profile: -w ghc-8.8.2 -O1
In order, the following will be built (use -v for more details):
 - repline-0.2.2.0 (lib) (configuration changed)
Configuring library for repline-0.2.2.0..
Preprocessing library for repline-0.2.2.0..
Building library for repline-0.2.2.0..
[1 of 1] Compiling System.Console.Repline ( src/System/Console/Repline.hs, /home/vanessa/git-builds/junk/repline-0.2.2.0/dist-newstyle/build/x86_64-linux/ghc-8.8.2/repline-0.2.2.0/build/System/Console/Repline.o ) [System.Console.Haskeline changed]

src/System/Console/Repline.hs:142:1: error:
    Could not load module ‘System.Console.Haskeline.MonadException’
    It is a member of the hidden package ‘haskeline-0.7.5.0’.
    Perhaps you need to add ‘haskeline’ to the build-depends in your .cabal file.
    Use -v (or `:set -v` in ghci) to see a list of the files searched for.
    |
142 | import System.Console.Haskeline.MonadException
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Since it's not needed with newer versions of base anyway

Since haskeline < 0.8 doesn't support GHC 8.10, that should also unblock compatibility with GHC 8.10.

I have a small project I'd like to transition from using raw haskeline to this library. However, I make a lot of use of getInputChar directly to do things like ask the user a yes/no follow-up question after a command, and the lifted version defined in the MonadHaskeline class isn't exported. In fact, as far as I can tell, it isn't ever used in this library apart from defining other instances of MonadHaskeline. Is there a good reason not to use getInputChar directly with repline, or perhaps a more idiomatic solution to the problem of getting follow-up answers?

Currently, there's a way to toggle multiline mode based on matching a specific commmand:

>>> :multi
... continuation

However, it would be nice to provide a way to toggle this mode based on parsing information, to make something like the following work

>>> incomplete expression (
... so REPL enters multiline mode )

A possible API for this would be:

beginMultiline :: HaskelineT m ()
endMultiline :: HaskelineT m ()
 -- returns a list of lines since the enclosing beginMultiline
 -- alternatively, this could be managed by the caller
multilineContext :: HaskelineT m [String]

allowing something like

cmd :: Command (HaskelineT IO)
cmd s = do
  context <- multilineContext
  if Parser.isIncomplete (context ++ [s])
    then beginMultiline
    else do
      endMultiline
      -- process (context ++ [s]) as a multi-line chunk

Stephen-man, all of your arguments against blockchain come from

a) envy
b) hence, bitterness

don't they?

Are they driven by the fact that you missed bitcoin for $0.1 in the past? As such, the only thing left for you is to critisize cryptocurrencies.

And don't recognize the crypto. Fight.

GHC 8.8 comes with a new and notably breaking version of haskeline that switches from using a bespoke MonadException to using the exceptions type class troika.

I am looking for a way to execute an rc file during initialisation phase.

Right now, all I can do is call "command" manually, but there is no
way to invoke the options parser manually. I'd have to reimplement options
parsing myself, which seems wrong.

The goal is to have something like .ghci, where :commands would also work as expected.

Thank you for creating a great library.

In docs, the abort function is said to abort and continue the REPL loop.

It works normally in the Command, but REPL does not restart in Options.

Is it intended?

import           Control.Monad.IO.Class (liftIO)
import           Data.List              (isPrefixOf)
import           System.Console.Repline

main :: IO ()
main = mainLoop

type Repl a = HaskelineT IO a

mainLoop :: IO ()
mainLoop = evalReplOpts replopts
  where
    replopts = ReplOpts
      { banner           = const (pure ">>> ")
      , command          = cmds
      , options          = opts
      , prefix           = Just ':'
      , multilineCommand = Nothing
      , tabComplete      = Word0 completer
      , initialiser      = ini
      , finaliser        = final
      }

final :: Repl ExitDecision
final = do
  liftIO $ putStrLn "GoodBye!\n"
  return Exit

ini :: Repl ()
ini = liftIO $ putStrLn "Hello, REPL"

cmds :: String -> Repl ()
cmds str = do
  liftIO $ print str
  abort

opts :: Options (HaskelineT IO)
opts =
  [ ("foo", foo)
  ]

completer :: Monad m => WordCompleter m
completer n = do
  let opts = [":foo"]
  return $ filter (isPrefixOf n) opts

foo :: String -> Repl ()
foo args = do
  liftIO $ print args
  abort

expected:

>>> :foo hello
"hello"
>>>

actual:

>>> :foo hello
"hello"
ghci> 

Sometimes I wish to store the history somewhere like ~/.local/, this will be more convenient for a shell-like application.

However, I've noticed that currently the history-related configurations seem to be hardcoded:

I think it would be nice if I could control these options while conserving all the niceties that come with this wrapper :)

Anyway, thanks a lot for making this project! 🙏

I would like to rewrite one of my program from python to haskell. My program relies on https://github.com/python-cmd2/cmd2 and makes extensive use of cmd2 autocompletion based on python's argparse parsers.
I was wondering if there was a similar possibility (out of the box) with repline to accept an optparse-applicative parser and autocompletes that Parser ?
If not do you know any similar library that would do it ?

I get the following error when I give one (or multiple) space as an option: ": "

>>> : 
src/System/Console/Repline.hs:207:15-37: Irrefutable pattern failed for pattern cmd : args

I can have a go at fixing it, I just thought I would report the issue first in case I don't get a fix for it.

Can we provide a way to exit from repl by Command like :quit in GHCi?
I'm ready to implement this