如何在空行上下文中运行sublime-text命令？

Question

I'd like to open a "sbcl" repl when I type 'repl' on an empty line in a lisp file.

I've got this keybinding so far,

[
    {
        "keys": ["r", "e", "p", "l"],
        "command": "run_existing_window_command",
        "args": {
            "id": "repl_sbcl",
            "file": "config/CommonLisp/Main.sublime-menu"
        },
        "context": [
            { "key": "selector", "operator": "equal", "operand": "source.lisp"},
        ]
    }
]

It works fine, except that it triggers in cases where I don't want it to trigger, ie, within code

(defun (bla) repl)

Or within comments

; repl

I only want it to trigger on empty lines, denoted with {HERE} (example code taken from the 'practical common lisp' book)

(defun dump-db ()
  (progn
    (format t "~%") ; print a newline, prettier in a repl
    (dolist (cd *songs*)
      (format t "~{~a:~10t~a~%~}~%" cd))))
{HERE}
(add-record
  (make-cd "Butterflies (On Luci's Way) - Demo" "*Shels" 8 nil))
{HERE}

How can I express this empty line constraint using Sublime's context ?

Edit: despite being the one asking this questions, I figured out that this is a really bad idea . Using bindings like "keys": ["r", "e", "p", "l"] will mess with your undo history. The interaction between Sublime's keybinding listeners and the history is that if add a handle like this, every single letter you type will be added to the undo history Very, very bad . Ctrl-z becomes a keyboard-mash-fest. :(

Answer 1

Just add a context to check that the preceding text on the line is empty (or consists only of rep or repl , depending whether the keys you press are added to the document or not before the keybinding operates - I'm not at a computer to check right now) and a context to check that the following text on the line is empty:

{ "key": "preceding_text", "operator": "regex_match", "operand": "^$|^repl?$", "match_all": true },
{ "key": "following_text", "operator": "regex_match", "operand": "^$", "match_all": true },

You can take a look at the default keybindings for more examples of using the preceding_text and following_text contexts. There are also some more details on the unofficial docs .

To exclude the key binding from operating in multi-line comments, you could change your selector to source.lisp - comment .

Answer 2

Based on the help from https://stackoverflow.com/a/45875699/2302759 , I came up with this configuration:

// opens an sbcl repl when you type 'repl' in a lisp context
{
    "keys": ["r", "e", "p", "l"],
    "command": "run_existing_window_command",
    "args": {
        "id": "repl_sbcl",
        "file": "config/CommonLisp/Main.sublime-menu"
    },
    "context": [
        { "key": "following_text", "operator": "regex_match", "operand": "^$", "match_all": true },
        { "key": "selector", "operator": "equal", "operand": "source.lisp"},
        { "key": "preceding_text", "operator": "regex_match", "operand": "^[repl]*", "match_all": true }
    ]
}

The first context matches end of line, the second context matches .lisp files only, lastly, the third context matches that there is nothing before the line except for potentially lingering 'repl' characters

The configuration matches the test-case perfectly now :)

(defun dump-db ()
  (progn
    (format t "~%") ; print a newline, prettier in a repl
    (dolist (cd *songs*)
      (format t "~{~a:~10t~a~%~}~%" cd))))
{HERE}
(add-record
  (make-cd "Butterflies (On Luci's Way) - Demo" "*Shels" 8 nil))
{HERE}