Built-in help text (not html) documentation for Racket xrepl - vim

I’m running racket as a repl (with xrepl), and I’m able to use ,doc to see some relevant documentation (almost awesome), but it fires up a web browser to see the documentation. I’d like to be able to see the docs right in the repl, similarly to how it’s presented in other repls (R, Clojure, ipython, pry, etc). Is this possible?
E.g., in Clojure’s lein repl, one can do:
user=> (doc map)
-------------------------
clojure.core/map
([f coll] [f c1 c2] [f c1 c2 c3] [f c1 c2 c3 & colls])
Returns a lazy sequence consisting of the result of applying ...
It would also be great to be able to see source ((source map) in clojure), but I haven’t seen any hints of this being available.
I happen to be using Vim (with slime/tmux), so any Vim-based solution would also work, probably tied to its K built-in help.

I'm not sure this is practical given the nature of Racket documentation.
The help deliverable is HTML.
Unlike Clojure (or Emacs Lisp), Racket doesn't have doc strings in the function definition source.
Racket docs don't have a convention like the one that the first line of a doc string should be a summary (a short-version to use in situations like a list of commands or in a REPL).
You can try xrepl's ,desc <id> command. Starting in Racket 6.1.1, if the function has installed documentation, it will print a rendering of the "blue box" -- the function signature with contracts and/or types. In many cases that's all you need, say to jog your memory. However there is no text describing the item. And if there is no installed help for a function, it won't attempt to show you anything based on the function's definition source.
So for example in racket-mode for Emacs, there is a racket-describe command and it does not fire up a browser -- but it shows the full HTML help (if any) using shr in a separate Emacs buffer. If there is no help, it does try to find the source and extract a contract/type and signature to show you. But again, there is no doc string in that source, to find, much less a one-line summary to show neatly in a REPL.
There are vim fans using Racket; the ones I know are use evil-mode in Emacs and feel it's the best of both worlds. However I appreciate that's not your current workflow using multiple languages, so I'm not proposing that as the solution for you.

I put together VROD, a solution that parses the reference documentation into something that Vim can work with. This provides essentially what you can get from clojure's doc built-in help, but through Vim’s K-help. And it also does some highlighting and shows examples.
(It also happens to do auto-completion of functions.)

Related

Can ack/ag/grep print function name?

Is it possible to print the function or class name in which a keyword occurs when using ack or ag? This is something I have highly desired for quite some time.
I think it would be quite tricky, as different programming languages have different ways of enclosing functions/classes.
Note that my goal right is for searching through C source code, however I would prefer a generic solution which covers more languages/syntax.
Author of ack here. No, I don't know of any greplike tool that understands anything about the text files that it's searching. It's something that people ask for all the time, but I've never even thought about implementing it.
You said "I think it would be quite tricky, as different programming languages have different ways of enclosing functions/classes." You're exactly right. Also, consider things like comments
/* void foo() */
and literal strings
printf( "void foo()" );
that would cause problems for any search tool. Neither of those instances of the string void foo() is actually a function declaration.
Check out the More Tools page on beyondgrep.com. Something like cscope might help you.
As commented by #Inian, it would be difficult to get a robust solution using ack, ag and grep as they are not aware of the grammar of the languages.
However, for my case of looking inside C source code files, I used ack with an OR condition to include lines which are starting with the function definitions. In my case, all my functions were either returning int or nothing. Hence, the following code printed out function definition lines alongwith the lines containing the KEYWORD:
ack 'KEYWORD|^void|^int'
Although none of the programs you listed currently have this functionality, Git uses language-based regexps to implement git grep -L (search within a function name). This blog post describes how it works. The current list of regexps are in the git source tree here, and can be extended as described in the blog above.
Also, ctags provides a universal way to enumerate tags from files of multiple languages, but I haven't (yet) found a way to integrate this output with git grep -L yet.

Vim-Sexp - How do I move each inner form to a new line?

I have the awesome vim-sexp and vim-sexp-mappings-for-regular-people plugins installed, and I've come across a situation I'm not sure how to solve.
Suppose I have the following form:
(alimony barbara (code determinant) eclair final-countdown)
How can I transform that to:
(alimony
barbara
(code determinant)
eclair
final-countdown)
I can go ahead and insert a newline before every inner-form/element, but that is a bit tedious. There should be a way with or without the sexp plugin
This is an old question, but maybe an updated answer will help someone who comes here in the future.
You don't have to write the program mentioned by Kaz. Others have already done it. I have not tried them, but here are a few:
fipp,
cljfmt,
cljstyle,
zprint,
joker. (The last one does more than code formatting.)
As Kaz suggests, once installed, you can pipe code to a formatter using !. You can even bind this operation to a key combination. Some of the formatters offer suggestions about how to do this sort of thing.
In addition, some vim IDE plugins, such as vim-iced provide support for using an external formatter.
A productive way to get this behavior would be, rather than fighting with Vim modules and extensions, to write a Lisp program which reads S-expressions and outputs them reformatted in the desired way. To use that program out of Vim, just pipe a range of lines into it using the ! command.

Where is SDL.P (Point constructor) defined?

I've attempted to comb the repository (oh the joys of globally used single character names) without luck, but maybe I'm looking for the wrong things.
Seeing documentation for SDL.P would probably also work.
For future reference, is there a good way to go about finding data constructors in Haskell (as they seem to be difficult to grep for in the single-character case)?
Hackage has haddocks for the sdl2 package. If you click the "Index" link, then click "P", you can find a list of all identifiers that start with that letter -- including the P data type.
http://hackage.haskell.org/package/sdl2-2.4.1.0/docs/doc-index-P.html
Is this it? It’s all I could find using stackage search within the “sdl2” package.
https://www.stackage.org/haddock/lts-12.13/sdl2-2.4.1.0/SDL-Internal-Vect.html#v:P
Edit, how I did it:
You can limit the search offered by Stackage to a single package, using the URL: https://www.stackage.org/package/PACKAGE_NAME, so in this case https://www.stackage.org/package/sdl2.
Searching for operators, put them in parentheses, such as "(.)". For your question, search for "P" like so: https://www.stackage.org/lts-12.13/hoogle?q=P&package=sdl2

Command-T for Emacs?

I'm a long time Emacs user, but partially switched to MacVim 2 years ago, and have been using it for all my programming work (still using Emacs for other stuff). I decided to switch back to Emacs now, mainly because of the awesome evil-mode. I'm quite happy, but I still haven't found something as good and simple as the Vim Command-T plugin.
The main problem with the Emacs alternatives is that they are either too complicated and or slow.
The closest thing to Command-T is helm/helm-cmd-t, but it doesn't quite work like it.
Let's say you have two paths:
app/controllers/admin/feedback_controller.rb
app/controllers/fee_controller.rb
In Vim's Command-T, you can write:
app/controllers/fe
And it will match both paths.
With helm-cmd-t, if I write app/controllers/fee, it will only match fee_controller. If I want to match both, I have to use a regexp, as in app/controllers/.*, which is not that bad, but requires more keystrokes.
Any suggestions appreciated!
Any Emacs package that uses ido can do this, provided that ido-flex-match is non-nil. Helm-cmd-t deliberately doesn't support this kind of flexible matching.
You can get the behaviour you describe using find-file-in-repository with ido-flex-match set to 't.
I've recently started using flx with ido-mode and projectile it has exceptionally good, ranked fuzzy matching and has a very similar feel to CtrlP and CmdT for Vim.
It can be installed via MELPA.
M-x package-install
flx
For more info see the flx project.
Here's a screengrab to illustrate...
Here it is, but required helm to be installed first: https://github.com/emacs-helm/helm-cmd-t
EDIT: See my Helm guide. Read why it is powerful. See helm with projectile in action in that section.
With fuzzy searcher like Ido + flx or the like in Vim, you have to type thing in order.
With Helm, you can perform out of order matching.I called it out of order because whether I enter "main.c x86" or "x86 main.c", I get the same set of results for the either query. But it also makes sense to call it multi-steps search. Without having to enter the search strings (called "patterns", which are actually regexp) in an orderly fashion, Helm gives me greater freedom: I can enter the thing I wanted first in my mind without having to remember its complex path; if there are many candidates from the target I wanted, I narrow it down further with more details (patterns).
The above example to illustrate the two cases from the advantage above:
If my desire target is not unique, fine I can narrow further.
If my desire target is unique, I can immediately get it.
As you can see, the Linux kernel source tree contains more than 40kfiles, and I narrowed it down to a few files immediately.
Visual Studio also implements this mechanism in their project search, but it's not generic as Helm. In Helm, you can reuse the same Helm interface for many other things; for example, see helm-semantic-or-imenu. You have something like an outline tree, but you can interactively and incrementally narrow to the candidates you want with a few simple patterns.
Finally, fyi, flx author - Le Wang - is using Helm.
Did you try LustyExplorer? It's based on the Vim plugin with the same name.
Also, it looks like you are not using Command-T to the best of its capabilities: acfe should be enough for it to match those two files. What you do is not particularly better than :e app/con*/**/fe<Tab>.
I've once run across gpicker which advertises speed as one of its advantages over Ido and other "native" elisp packages. Never got to try it out on real-world projects though, but it might work for you.
Long story short - there's nothing quite like command-T for Emacs. Best options are gpicker or Peepcode's peepopen, but they are external applications, and I find them to be distracting after using command-T for so long. I'll stick to MacVim for now, only because of command-T, but might look into implementing something that behaves just like command-T as an exercise.
Thank you all for the answers and comments!
Give textmate.el a try :)
https://github.com/defunkt/textmate.el
You'll just have to use "Command+T" instead of "Ctrl+P" :)
https://github.com/bling/fzf.el
This is the best solution out there in my opinion. Here's why:
Uses projectile to determine project root if you're in a project.
Otherwise it very quickly indexes the file in the current directory.
Fuzzy matching.
Can be customized (top or bottom placement, number of records, etc.)

Using Emacs for big big projects

Maybe is a often repeated question here, but i can't find anything similar with the search.
The point is that i like to use Emacs for my personal projects, usually very small applications using C or python, but i was wondering how to use it also for my work, in which we have project with about 10k files of source code, so is veeeery big (actually i am using source insight, that is very nice tool, but only for windows), questions are:
Searching: Which is the most convenient way to search a string within the whole project?
Navigating throught the function: I mean something like putting the cursor over a function, define, var, and going to the definition
Refactoring
Also if you have any experience with this and want to share your thoughts i will consider it highly interesting.
Br
The "traditional" way of navigating C source files is to use "etags" to make a file called TAGS, then use ALT-. to go to functions across files.
For searching for strings in files, I usually use "grep". You could make a shell script with all the directories you want to search or something if you get tired of typing them in each time.
My projects typically live in git, so I put this together to quickly search them:
;; There's something similar (but fancier) in vc-git.el: vc-git-grep
;; -I means don't search through binary files
(defcustom git-grep-switches "--extended-regexp -I -n --ignore-case"
"Switches to pass to `git grep'."
:type 'string)
(defun git-grep (command-args)
(interactive
(list (read-shell-command "Run git-grep (like this): "
(format "git grep %s -e "
git-grep-switches)
'git-grep-history)))
(let ((grep-use-null-device nil))
(grep command-args)))
There is also the Emacs Code Browser. It makes exploring projects a lot simpler. See here and here for more information.
Regarding searches in the whole project, I find extremely useful the rgrep command.
Also, imenu is quite handy to jump to a function definition in the same file.
These are my 2p.
look to EDE from CEDET - it provide base support for projects...
ECB is too heavyweight for my taste. I have had good results with xcscope. Needless to say it doesn't help too much with Python.
http://www.emacswiki.org/emacs/CScopeAndEmacs
In addition to using TAGS as others have mentioned, I find igrep and igrep-find very useful. There is also Emacs' built in grep and grep-find, but I find their interface more clumsy.
My standard search is:
M-x igrep-find some_regexp RET ~/work_area/*.cxx
Which will look for all *.cxx files under ~/work/area, and show results matching some_regexp. Like all the search utilities, it populates a compilation-like buffer you can navigate using C-x ` (aka M-x next-error).
There are many ways that Icicles can help with projects. Likewise, Bookmark+ and even Dired+.
These libraries can help you create, organize, and manage projects, wherever their files and directories might reside. And they can help you navigate and search in various ways.
Some of the features are unique -- quite different from other approaches. I could list some of the project support here, but this is the best place to start.

Resources