I am new to Atom / Stack / Haskell and after a fair bit of hand wringing managed to get set up on my windows 10 box.
One thing I am still stumped on is finding a way to set up interactive evaluation from within Atom (like "debugging" in Leksah)?
I have installed the "Script" which looks promising but all I get is:
'ghc' is not recognized as an internal or external command,operable program or batch file.
I presume I need some kind of configuration but I can't work out what's required. I think need a way to pipe through to an open ghci console.
Is there a way of setting this up with "Script"or any similar package?
Thanks
John
as you checked for yourself the ide-haskell-repl atom-package should work here
Related
I'm coding a Rust app and since it's fairly small and there don't appear to be any stable UI frameworks, I've made it run in the console using println! and whatnot for input/output. However since this program is intended to be used by people directly after downloading from the internet (due to its use case), they're likely to just double click on it instead of navigating to their downloads directory in a terminal and running it from there.
This is a problem because on Linux, it runs in the background waiting for input and looks like it's not working. On Windows, Rust programs do open in CMD by default. (and in fact many of the search results for my question were about disabling this behavior - the exact opposite of what I want!).
So is it possible to somehow make my application open in the system's default terminal? My preferred way would be to somehow embed in the executable to open in terminal (similar to the -mconsole compiler flag on MinGW). Otherwise would it be possible to detect it's in the background and fork it into a terminal? If that's not possible then is it at least possible to detect that the app is not running in a terminal and throw up a message box telling the user to run in a terminal?
My app is cross-platform but I'm OK with writing code conditionally compiled on one OS.
One typical way would be to distribute a program.sh along with your executable. If .sh extension is bound to opening a terminal in their window manager of choice, it would open automatically. If not - it is enough of a hint for running it from the shell.
Without this file you could:
Detect if the program is already running inside a terminal can be done with isatty(). There's a crate for it.
If not, spawn the terminal app process (see process::Command) and relaunch the program with it by passing its path to the terminal command line options. As #Caesar mentioned there's a bunch of popular terminals that you might want to check for presence on Linux. If nothing is found, xterm could sometimes be a fallback.
Working with Pure Data, trying to record audio output from a patch I've made, and am 1) unable to create a file within pure data to write to and 2) attempting to use the writesf~ object causes the program to freeze after about two to three seconds. I suspect the two things are related- perhaps the program is attempting to write data somewhere, somehow, but it's going in the wrong place or some such and causing the program to freeze?
I've uninstalled the latest Pure Data release (0.51-1) and installed an earlier stable release (0.5-2) and even tried an alternative called "purr data (latest release)" all with the exact same result on my windows 10 acer laptop: no file created, and program freezes after a few seconds.
I'm testing with this patch:
I first click on the message that reads "open rec.wav" then the start then the stop, and if I take longer than three or so seconds to click on "stop" the program freezes, otherwise nothing at all happens.
I have performed system wide search for the audio file, including the folder that the patch is in, all to no avail.
Any trouble shooting hints will be carefully attempted.
Are you sure you have write-permissions on the target directory?
If your example you use rec.wav which has no explicit target directory (and is just using the "current", so it's hard to tell from outside what this directory would be).
#max-n's answer suggests to use /tmp/foo.wav which is an illegal directory on Windows. Due to a known bug, using an illegal (or otherwise non-writable) path will lock up Pd.
If your "current" directory happens to be your system root (aka C:\), you might well lack the permissions to write there.
You could check by starting the Pd from the cmdline and see whether the terminal spits out any weird errors:
⊞ Win+R
type cmd and hit Enter
in the opening terminal type the full path to your Pd-executable, e.g.:
C:\Program Files\Pd\bin\pd + Enter
(ideally leave out the extension (that is: use .../pd rather than .../pd.exe)
If the problem is indeed a permission problem, you can simply work around it by specifying the full path of the output file (and make sure that it is in a writable directory).
The easiest way to do this is by using a file-selector to choose the output file:
[bang(
|
[savepanel]
|
[open $1(
|
[writesf~]
There might be a reason why the helpfile uses a [delay 1000] to schedule a stop message in a predefined time.
Using the Turtle shell scripting library I am trying to launch a program, i.e:
shell "vim" empty
The problem is that this yields the warning Warning: Input is not from a terminal and causes Vim to lag for a few seconds before finally launching.
Questions:
Is shell the best Turtle function to launch an external program from haskell?
If so, is there any way to get around errors like the above?
You want to use functions from the process library, specifically createProcess or runProcess.
Relevant turtle thread on the issue here.
Example usage.
You could try manually setting up I/O to the vty. E.g. in bash: vim < $TTY > $TTY. I guess turtle is doing that with its own file descriptors under the hood, based on the warning, so you should be able to manually set up those redirects (or just use the command I gave via shell). You just need to make sure you've got a TTY environment var around.
I want to run following Linux command which opens the document with application registered with the system:
xdg-open mydocument.pdf
I see that many commands for this are available: run, run*, capture, shell, execute, system* etc.
from: http://wiki.call-cc.org/eggref/4/shell and https://wiki.call-cc.org/man/4/Unit%20utils
I also need the result of the command (ran successfully or not) from this.
Following (system without *), although not listed, also seem to work well:
(define result (system "xdg-open mydocument.pdf"))
Which of these will be the safest way to run system commands as above?
If the name of the document is hardcoded, it doesn't matter much what you use. If the file name is user-supplied, you must use qs to quote the arguments if you're relying on a string-based API like system's. It might be easier to pass arguments separately using process.
I don't know the shell egg very well, but if you want to get really fancy with shell calls, the scsh-process egg is a very nice alternative (full disclosure: I'm its author).
Let's take an example. When I run:
xkbprint $DISPLAY keyboard.ps
what happens in the system? I would like to know how the X really work because I regularly get nasty error reports such as
Fatal Error: Cannot load geometry for /tmp/launch-NawGIk/:0
Exiting
I know that the X11 was designed in a way that it is easy to extend. But how? How does the X11 protocol work? How do the X extensions work?
Whatever happens, I'm pretty certain it isn't going to be what you expect.
The syntax of xkbprint(1) is
$ xkbprint sourcefile destfile
and sourcefile should be a compiled xkb file. $DISPLAY is going to resolve to something like mymachine:0.0, which isn't a very reasonable file name.
Actually, since you're running a Mac, it's echoing exactly what it's seeing: /tmp/launch-NawGIk/:0 is the special OS/X magic to let launchd run X apps. The error message means that it's not finding a geometry or display in that file. Which is no surprise since there is no file named `/tmp/launch-NawGIk/:0
Try reading the man page, and see if you don't have more luck with a compiled .xkm file.
More generally, if you want a starting introduction to X, try this article.
Man xkbprint says:
The xkbprint comman generates a
printable or encapsulated PostScript
description of the XKB keyboard
description specified by source. The
source can be any compiled keymap
(.xkm) file that includes a geometry
description or an X display
specification.
As Charlie Martin pointed out, xkbprint is misusing your $DISPLAY as a file name. Try specifying the display more precisely, to avoid ambiguity with file name. Try man xhost. Maybe passing simple ":0" will fix the problem?