Is GUI debugging available for embedded languages in DrRacket IDE? - racket

I am experimenting with Rosette (https://github.com/emina/rosette), an s-exp language embedded in racket. I want to step through a rosette program using GUI debugging facilities in DrRacket IDE. However, unlike a racket program, the execution of a rosette program in debug mode doesn't pause at the top-most expression; as soon as I click on the debug button, it runs through to completion. Consequently, I have no way of observing intermediate execution states.
This makes me wonder if DrRacket IDE's debugging facilities are available to embedded s-exp languages.

I hate to say this, but I don't think there is a way, built in. But DrRacket is very extensible, so I'm guessing there might be a plugin.
And feel free to write one!

Related

Is it possible for Emacs to show Erlang functions arity in echo area like for Elisp functions?

I've installed and configured Erlang language in my Emacs dotfiles, mostly following this guide: https://erlang-ls.github.io/editors/emacs/
But I'm just starting in Erlang and I don't really know how a Erlang development environment looks like, so I'm not sure if things "missing" aren't part of the Erlang development environment or if it's something I have configured wrong.
This is my current configuration: https://github.com/jacksonbenete/.emacs.d/blob/main/lm-emacs/languages/erlang.el
I don't have functions completions, it asks for a "tags-table" and I don't know what it is or where I can find it.
Also, I don't receive any hints in the echo-area, this would be very useful and it's my main question since I can live without completion.
Just like I can start writing a function in Lisp and receive some hints of arity and parameters in the echo area/minibuffer, can I receive the same hints while writing Erlang?
Maybe my lsp-server isn't configured correctly?
Or this is not something implemented for Erlang-mode and Erlang-ls?
edts is the way to go with emacs, it has autocomplete and code navigation. Originally I was using distel, but after this presentation I switched to edts
I compiled it with erlang 23.0, but once it is compiled, I develop on other versions without problems, like currently I'm using erlang 24.0
For managing different erlang versions on my system, I'm using kerl
This is my personal emacs configuration, I got most of it from internet and then I did personal customizations
Other than that, I use the templates that came with the erlang mode a lot (tempo-template-erlang-*)

IDE support for Scala scripting

I plan to try some exploratory programming with Scala, e.g. loading some scala source files and call the functions defined in these source files interactively, maybe doing some plotting in the between.
I want to keep a scripting source file, and occasionally send some lines in it to the scala console using a short-cut such as Ctrl+Enter.
Which IDE supports scripting well?
The Scala plugin for Eclipse offers two different interpreters. One is the standard REPL, simply integrated within the IDE, the other one is the Run Selection Interpreter which may be very handy for the kind of experimentation you'd like to do, give it a try.
The Scala plugin for eclipse is the best out there .
http://www.scala-ide.org/
With the Run Selection Interpreter you can achieve what you want :
An expression can be executed in the interpreter by selecting text in
any Scala editor and either selecting the toolbar button (see
screenshot) or by using the Ctrl+Shift+X key combination (Cmd+Shift+X
on the Mac). The key combination can be changed by going to Keys ->
Preferences and changing the binding for the command "Send Selection
to Scala Interpreter"
In latest version of scala plugin for IntellJ Idea 11 (Nika EAP) scala console works much better. Read more in plugin blog http://blog.jetbrains.com/scala/2011/10/19/scala-language-console-nika-builds/
you can try Slate while I am still heavily developing. Although, for basic scripting, you can probably do command line as well. Almost all IDEs support integration with the interpreter btw.
It is obligatory to mention emacs here. Can emacs do _? Yes, emacs can do that!
In all seriousness, though, you might want to google around for "scala mode emacs" and see what you can find.

Emacs for Erlang with vi like keybindings and handy short references?

I have come accross vi-style keybindings for Emacs, but my past experience in mixing Lisp based config in .emacs file for enabling various modes etc., hasn't been very pleasant so far.
Read several articles on Emacs + Erlang, but is there something that might be slightly easier for folks familiar mostly with vi (and who are unfamiliar with Lisp)?
The entire set of possibilities (keybindings) is quite overwhelming. Is there a condensed key-map/shortcuts reference specially relevant for Erlang development?
Just use vi and a command line. There are numerous people doing that and it seems to work just fine for them. Even though I use Emacs, it is not the Emacs-erlang interaction I use. Rather I usually just have a separate Erlang shell and then I load modules in that shell with the l() command for interaction.
Answering your questions one by one:
Debugging in Erlang is funny. Firstly, if your program is kept functional you will find that you need much less debugging to figure out what the program does incorrectly because you can simply write small tests for each of the numerous functions to test its correctness. And you can add those into unit-test frameworks.
As soon as you add multiple processes to the mix you will find that traditional debugging doesn't work anymore anyway. The trick is then to trace and assert, and you will need to learn a way to read programs without running them and see where they go with a debugger.
That said, try to execute debugger:start() in an Erlang shell :) There are also the tracing systems and redbug, a 3rd party tool built on top of them (part of the eper suite).
Profiling can be done with one of the 3-4 profilers: cprof, eprof and fprof are all slightly different in scope and in how much impact they have on your program and if they can be run on a production system or not. I tend to use eprof and I have a knob in my program which will spawn an eprof and then attach it at program start.
Try appmon:start() in a shell.
The standard vi-way of browsing large code bases is to create tags-files so you can jump to the definition point of the thing-under-the-cursor. Emacs can do the same. I have a make tags target to create these files so I can easily make jumps around in the source code. When jumping you have a stack of the former jumps so you can return to the point you jumped from later on.
Finally there are tools like xref which can be worked to create call graphs and find odd things in the code. It will require some coding on your part, but it does provide you with the necessary tooling.
Viper mode provides Vi-style keybindings. That's probably the easiest way to start. Enabling a new mode in your .emacs is a pretty fundamental part of using Emacs, so it's a learning hurdle best cleared early!
The Emacs manual contains more detailed information about making individual changes to your keybindings.
You may find Xah's keybinding tutorial helpful, as it provides many examples.

Eclipse Style Function Completions in Emacs for C, C++ and JAVA?

How Do I Get Eclipse Style Function Completions in Emacs for C, C++ and JAVA?
I love the power of the Emacs text editor but the lack of an "intellisense" feature
leaves me using Eclipse.
M-/ is a quick and dirty autocomplete based on the contents of your current buffer. It won't give you everything you get in Eclipse but is surprisingly powerful.
I can only answer your question as one who has not used Eclipse much. But! What if there was a really nice fast heuristic analysis of everything you typed or looked at in your emacs buffers, and you got smart completion over all that everywhere, not just in code?
M-x load-library completion
M-x global-set-key C-RET complete RET
When I was doing java development I used to use the:
Java Development Environment for Emacs (JDEE)
The JDEE will provide method name completion when you explicitly invoke a jdee provided function. It has a keyboard binding for this functionality in the jdee-mode.
The CEDET package provides completion for C/C++ & Java (and for some other languages). To initial customization you can take my config that i use to work with C++ projects
Right now, I'm using Auto Complete for Emacs. As a current Visual Studio and ex-Eclipse user, I can say that it rivals both applications quite well. It's still not as good as Microsoft's IntelliSense for C#, but some would say that C++ is notoriously difficult to parse.
It leverages the power of (I believe) the Semantic package from Cedet, and I find it feels nicer to use when compared to Smart Complete. It completes C++ members, local variables, etc. It's pretty good. However, it falls down on not being able to complete overloaded methods (it only shows the function once with no parameters, but thats a limitation of Cedet I believe), and other various things. It may improve in future though!
By the way, I could be wrong here, but I think you need an EDE project set up for the class member completion to work (just like you would normally with Semantic). I've only ever used it while having an EDE project, so I assume this is true.
Searching the web I find http://www.emacswiki.org/cgi-bin/wiki/EmacsTags#toc7 describing complete-tab in etags. It is bound to M-Tab by default. This binding may be a problem for you
Also, etags has some limits, which may annoy you...
The link also points to CEDET as having better symbol completion support.
Have you tried the emacs plugin for eclipse?
http://people.csail.mit.edu/adonovan/hacks/eclipse-emacs.html
I've written a C++-specific package on top of CEDET that might provide
what you want. It provides an Eclipse-like function arguments hint.
Overloaded functions are supported both for function arguments hint
and for completion.
Package is located here:
https://github.com/abo-abo/function-args
Make sure to check out the nice screenshot:
https://raw.github.com/abo-abo/function-args/master/doc/screenshot-1.png
auto-complete-clang is what you want. Can't go wrong with using an actual C++ compiler for completions.
The only problem it has is there's no way to know what -I and -D flags to pass to the compiler. There are packages for emacs that let you declare projects and then you can use that.
Personally, I use CMake for all C and C++ work so I wrote some CMake code to pass that information to emacs through directory-local variables. It works, but I'm thinking of writing a package that calls cmake from emacs so there's less intrusion.

Writing Emacs extensions in languages other than Lisp

I'd like to take an existing application (written in OCaml) and create an Emacs "interface" for it (like, for example, the Emacs GDB mode). I would prefer to do this without writing a ton of Lisp code. In MVC terms, I'd like for the View to be Emacs, but for the Model and Controller to remain (primarily) OCaml.
Does anybody know of a way to write Emacs extensions in a language other than Lisp? This could either take the form of bindings to the Emacs extension API in some other language (e.g., making OCaml a first-class Emacs extension language) or an Emacs interaction mode where, for example, the extension has a pipe into which it can write Emacs Lisp expressions and read out result values.
http://www.emacswiki.org/cgi-bin/emacs-en?CategoryExtensionLanguage is a list of all non-Elisp extension languages you can use.
It does appear to be dynamic language centric.
http://common-lisp.net/project/slime/ is missing from that list, as it is not quite an extension language, but an Elisp-Common Lisp bridge. Its source code would show how to communicate back and forth over sockets.
A similar IDE for Erlang is Distel, at http://fresh.homeunix.net/~luke/distel/ (currently down) and https://github.com/massemanet/distel.
Good luck!
I don't know if this will work for your particular problem, but I have been doing something similar using the shell-command-to-string function:
(shell-command-to-string
"bash -c \"script-to-exec args\"")
So for example, we have existing scripts written in python which will mangle a file, so the above lets me invoke the script via emacs lisp.
A quick google search found this page describing a system to write extensions in Python, so it seems feasible to do what you want... you will just have to see if anyone has written a similar framework for OCaml.
Some Extension Api is now possible with the incoming emacs 25.1 and dynamic modules
A Library, emacs-ffi offer a foreign function interface based on libffi.
Check out complete documentation on the README.
Try PyMacs, which allows extending Emacs in Python.
edit: updated link.
From the statically typed languages side, there is something that looks quite performant and well featured for Haskell:
https://github.com/knupfer/haskell-emacs
there is also probably something useful for Scala to be reused from the Ensime project (has a bridge for both Emacs and Vim):
https://github.com/ensime/ensime-server
Furthermore, a quick google search revealed another potential candidate for extending Emacs with a classic FP language, OCaml; the project has a lot of .ml source files so there's got to be an Emacs-OCaml bridge somewhere:
https://github.com/the-lambda-church/merlin
There is no "Extension API". Emacs Lisp is way in there, and it ain't moving.
You can run Emacs commands from your other process. Have a look at Gnuserv.
There are plenty of applications where Emacs is the View for a Model/Controller in a separate process. The Emacs GDB interface is a good example. I'm not sure of a simpler example, maybe sql-postgresql?