Thanks very much, Judah! Given this info, there's a fairly easy emacs haskell-mode work-around. I made a shell script "ghci-no-tty" in my ~/bin that contains # So ghci+readline won't echo input cat | /usr/local/bin/ghci $* and used "M-x customize-group" with the "haskell" group to set the "Haskell Program Name" variable to "/home/conal/bin/ghci-no-tty" (must be full path). Now there's no more input echoing, and commands like automatic signature insertion ("\C-c\C-t") work again. Hooray! - Conal On Sun, Nov 16, 2008 at 10:31 PM, Judah Jacobson wrote:

2008/11/16 Conal Elliott :

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I'm still looking for a solution to this problem. I've heard from a few people who are affected also, but not any solution.

Barring a solution to ghci's behavior, does someone have an emacs-based workaround?

- Conal

On Tue, Nov 11, 2008 at 4:41 PM, Conal Elliott wrote:

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ghci echoes all of my input in emacs, when run via haskell-mode or via "M-x shell", which then confuses various useful haskell-mode features.

I

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built it from sources. At the time I didn't have libedit-dev, so today I installed libedit-dev (version 2.11~20080614 on ubuntu), did a clean make & install, and I get exactly the same behavior.

Does anyone have experience in getting through this problem? Willing to help me out?

Thanks,

- Conal

Hi Conal,

The problem is that eshell tells subprocesses that they're running in a terminal (e.g., when queried via hIsTerminalDevice), but always echos user input itself regardless of the tty's ECHO attribute. This confuses libedit, which assumes that if it's connected to a terminal then it can turn off echoing in order to run its own rich line editor.

In "M-x shell", you can work around this issue by starting ghci with, for example, "cat | ghci" to prevent ghci and libedit from trying to run as if in a terminal. Probably something similar could be done for haskell-mode; I'm not familiar enough with emacs to fix it myself.

Incidentally, googling revealed that zsh has a similar issue: http://www.zsh.org/mla/users/2001/msg00014.html (section 3.10)

Hope that helps, -Judah