Is there a short way to wrap an s-expression using slime?
Suppose i have finished some piece of code and I realize I need a variable (e.g. for efficiency reasons) and therefore want to wrap it with let or want to make it tail recursive and need to wrap it with labels, what is the fastest way to do this? Is there a shortcut?
IntelliJ (a Java IDE) allows things like:
x > 3.if + TAB
yielding
if (x > 3) {
}
So are there any "sexp-wrapping" shortcuts (postfix or prefix) in slime/emacs?
The bar represents the cursor.
With paredit
There is a wrap-round command, bound to M-(. But when adding context to an expression, I generally do as follows:
|code
Open the parenthesis (the closing one is added automatically):
(|)code
... type ...
(let |)code
Call paredit-forward-slurp-sexp (C-right)
(let | code)
See also the The Animated Guide to Paredit.
Without paredit
|code
Call mark-sexp (C-M-Space), then kill the region; type and yank (paste) the text where you need it.
See also Expressions with Balanced Parentheses (e.g. forward-sexp), available in Emacs.
In python mode, when I forward-word. The cursor jumps from H to d (Hello_World). But in another mode(shell-mode or c-mode), the cursor jumps from H to _.
I want the result which i get in Python mode, even in the other mode. What should I do?
PS: I saw a similar question before, I have searched, but I could't find it.
I think you're looking for this:
(modify-syntax-entry ?_ "w")
Underscores will be treated as part of a word. This command will change the syntax table of the mode you're currently in. AFAIK there's no way to change syntax globally. However, you could try modifying the standard syntax table. Most major modes inherit the standard-syntax-table.
(modify-syntax-entry ?_ "w" standard-syntax-table)
If that doesn't work, I guess you have to add mode-hooks for all modes you're using and modify their syntax tables individually.
Things got a little simpler since Emacs 24.4. There's now a M-x superword-mode that has the desired effect.
I have wrote simple macro to define interactive function and bind it to key at same time
(That what my previous question related)
The only thing, that annoy me, that it looks ugly without highlighting.
It called such way:
(define-and-bind-command foo "C-x £" (message "Hello world"))
I want define-and-bind-command and foo be highlighted.
Well, to get define-and-bind-command highlighted, I can use wrapper around defmacro,
altho is not so pretty, and I have no idea about foo.
I know it is possible, because argument of require is highlighted with const face.
Or, probably, I am inventing wheel, and there is an another lisp mode with more
advanced highlighting?
highlighting the 'define-and-bind-command' can be achieved very easily using 'font-lock-add-keywords', usage would be
(defun my-elisp-mode-keywords()
(font-lock-add-keywords nil
'(
("\\<\\(define-and-bind-command\\)" . 'font-lock-keyword-face)
)
)
)
Of course you could change the 'font-lock-keyword-face' to any face of your liking or create and use your own face. You can find the name for a face already used very easy by moving the point (cursor) over the font-locked part of text and entering 'describe-face' followed by a return.
Edit2: Oh and of course you need to hook that defun to some hook, for elisp mode that would be:
(add-hook 'emacs-lisp-mode-hook 'my-elisp-mode-keywords)
Highlighting the foo part can be done using a regexp.
Unfortunately I can not yet help you with that part because I'm not sure how to match a regexp containing the 'define-and-bind-command' but highlighting only the word after.
Edit: unless you want to highlight both the 'define-and-bind-command' and the foo part in the same face, then it should be very easy. But I guess you want them to have different faces?
Edit3: Corrected my code, stackoverflow ate some braces before...
Edit4: Okay, I have a solution for matching the second part only, I have not tested it extensively but it seems to work. I have allowed for foo to contains any character but a space (and newline I think), I guess one could restrict that event futher to a-zA-z0-9 and "-", so feel free to change that to your liking. The Code responsible for matching only the foo part is
("\\bdefine-and-bind-command\s\\([^\s]*\\)" 1 'font-lock-function-name-face t)
Insert that in the line after the other font-lock keyword in the above function and you're good to go. The regexp matches 'define-and-bind-command' which must begin a word (that's the \b for) followed by a space and then it returns (font-locks) everything followed until a space exists.
Hope this helps!
font-lock-add-keywords can take a symbol, the mode to which to apply the new keywords. So you could do
(font-lock-add-keywords
'emacs-lisp-mode
'(("\\<\\(define-and-bind-command\\)" . 'font-lock-keyword-face)))
The disadvantage compared to using a function and a hook is that this doesn't work for derived modes; that is, if you have a mode which is derived from emacs-lisp-mode, it will not inherit these keywords.
What would be the easiest way to have the same kind of behavior that is in vim for the word back and forth navigation? In vim when you press "w" it moves a cursor forward one word, where word consists of a sequence of letters, digits and underscores, or a sequence of other non-blank characters, separated with white space (spaces, tabs, eol). In emacs on the other hand it skips until the end of the next word and the word is defined per mode in the syntax table.
For example: having a cursor at the beginning of the line following shows where vim put a cursor when you do forward-word ("w") operation:
opt1.arg = opt2.arg
^ ^^ ^ ^ ^^ ^
In emacs it is like:
opt1.arg = opt2.arg
^ ^ ^ ^ ^
It really depends on a one's preference, but I tend to like the vim style better and I was wondering what is the easiest way to have the same in emacs. I guess I'm not alone who switched from vim to emacs so perhaps someone already has a solution, ideally for the kill-word and backward-kill-word as well :)
I know you can get something similar by combination of M-f, M-b etc., but that is not the point. I also don't want to start a discussion which approach is better - the topis is well discussed in here.
You can actually use 'viper-forward-word
(require 'viper)
(global-set-key (kbd "M-f") 'viper-forward-word)
(global-set-key (kbd "M-b") 'viper-backward-word)
Mostly a duplicate of this, which says:
(require 'misc)
Then bind whatever keys you want to forward-to-word and backward-to-word. For killing, create some simple functions that wrap these functions and do kill.
I don't know why jpkotta's answer was deleted, but here it is again:
I have a minor mode that changes word-based commands to operate on syntax changes (and also CamelCaseSubwords). It may be a bit too fine-grained for some tastes, but I find I basically ever use single character movement anymore.
https://bitbucket.org/jpkotta/syntax-subword
# mods, I don't know why this answer would be deleted, so if you choose to delete this answer too, I'd appreciate an explanation.
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I try to keep my fingers on home row as much as possible.
Typing all the parentheses makes me move away from there a fair bit.
I use Emacs; the parentheses themselves are no issue, I'm comfortable with them. And I don't like modes that type them for me automatically.
I've thought about remapping the square brackets to parentheses and vice versa. Is this a good idea? What does everyone else do?
I would personally recommend the lethal combo of Emacs, SLIME & paredit.el
Paredit allows you to pseudo-semantically edit the LISP code at sexp level, and that makes the parentheses disappear almost completely. You can move around sexps as if they are simple words and even mutate them with just a couple of key-strokes. There is also a minor mode called Redshank which works in conjunction with Paredit and that provides more power.
Consider simple these examples (| is the position of the cursor):
(foo bar (baz| quux) zot) + C-( => (foo (bar baz| quux) zot)
(foo (bar |baz) quux zot) + C-) => (foo (bar |baz quux) zot)
(foo (bar baz |quux) zot) + C-{ => (foo bar (baz |quux) zot)
(foo (bar |baz quux) zot) + C-} => (foo (bar |baz) quux zot)
I have done some serious Common Lisp programming in my time, and paredit has proved to be invaluable to me. I can't even think of writing non-trivial LISP code without my toolbox. And after all that's the way it should be; you should never have to count or match your parentheses... once you master Paredit, the parentheses will just disappear from in front of your eyes.
Remapping the [] to () will help, but you will stop caring much after you start using Paredit.
Feel free to use the LISP specific portions from my dot-emacs.
With many non-US keyboard layouts, typing square brackets or braces is even more cumbersome than typing parentheses, anyway, which makes programming in most languages very strainful, so consider yourself lucky. ;)
As for me, I use a programmer-friendly non-standard keyboard layout that lets me type parentheses via [Super]-j and [Super]-k.
I have foot pedals. LeftFoot = open paren, RightFoot = close paren.
Well, I don't, but I don't use Lisp. It doesn't seem like a bad idea, though.
Could you imagine a variation on Lisp that used indentation instead of parens? (taking a page from the Python spec)
I take my fingers off the home keys....
I tried remapping in Emacs, but it creates new problems: say you're editing in a terminal window through ssh and you paste a snippet into the window; then parens and brackets get swapped in your pasting, not just your typing. If you try this, remap at a lower level in your system, like xmodmap.
(Of course, the obvious other problem is using other computers without your remapping. That was a nuisance too, though bearable.)
"... so many parenethesis"
The first thing I did was bind the '(' key to the sequence '('+')'+right(), so my parenthesis auto balance, leaving half as many left to type when writing new code.
You also want a convenient way to navigate out one paren -- bind C-] to the sequence search(')')+right(). Authoring becomes shorter now, as you don't need to take hands off the home position -- just type C-] every time you complete an S-expr.
Next thing I did was bind a key to a subroutine that pushes an existing item onto the current list ... so if // is the cursor position, then this command will transform:
(if (< //) (+ x 1)
(x)
(y))
to
(if (< (+ x 1) //)
(x)
(y))
Effectively pushing one item from the right into the current list -- very useful for editing existing code. The sequence '(', '<', C-S-], Space, '2' adds "compare less than 2" to an existing expression. Combined with C-], this lets you build new expressions very quickly from existing ones.
#jamesnvc,
I didn't think about binding () to [] keys... I'll have to try that, thx!
I remapped [] to () with xmodmap and like it. It was a bit weird getting used to writing code in languages that use [], but like any change, you get used to it. Having unshifted parens in Lisp is nicer than not having unshifted brackets in other languages, so it works out.
Anyway, here is the necessary xmodmap incantation for my US keyboard:
!! swap () and []
keycode 18 = 9 bracketleft
keycode 19 = 0 bracketright
keycode 34 = parenleft braceleft
keycode 35 = parenright braceright
I have to take my fingers off the home row to reach all the other shift-number operators, so I never thought about it much.
And once you type a left-parens, electric-parens give you the right.
If you use the parentheses more than the square brackets, by all means, remap away. I don't see how it could pose any more problems than, say, a lefty swapping her mouse buttons.
When I'm writing code, I generally spend much more time thinking and reading my code, than I do typing it. I've tried a couple of times in the past to switch to the Dvorak keyboard layout, but I lack obvious motivation because I can type much faster than I can think. Programming language syntax is a similar issue - as long as I can type code without leaving the keyboard (ie. using the mouse would be bad), I'm happy.
DrScheme has the keystrokes for parens and square braces flipped by default. It also has a feature where it magically guesses which one of the two you meant, so you rarely reach for shift-9.
Quack has a similar feature to that of DrScheme.
DivaScheme (my editor), is something completely different. It edits at the sexp level, so that the parens are no longer in the way.
Mostly, I just type them, but occasionally, I use M-( and M-) (especially when I am adding a LET binding "late in the stage"), to enclose the relevant nnumber of expressions.
I also changed my (dvorak) keyboard layout (via xmodmap) to switch the brackets ("[]") and parens, in conjunction with paredit-mode (which does indeed take some getting used to).
I use paredit and pair-mode packages but, for fast parenthesis typing I use electric-dot-and-dash to replace a double period in a () on a 5 ms delay (if I type slowly I get two dots then). It's a wonderful package (I hacked a bit for my personal preference; as I type with Dvorak keyboard, I replaced the dash key by a slash (// is not so common in lisp)).
To avoid the mess in parens, I add a package named 'highlight-parentheses to my tool set, and for maximum efficiency on sexp grabbings or text navigation in general, I also use vimpulse (as I am a Vim addict).
Rebind capslock to "(" and have the editor autoinsert ")" for you.
(This also helps for other languages with a lot of brackets, for instance HTML...)
I use Vim with vim-sexp and vim-sexp-mappings-for-regular-people then have mapped <leader>u to put me in normal mode inside of a new (.
map <leader>u i(