Removed hardcoded path, fix for first time not creating playground basedir (#7)

* Reworked this since it didnt work for me at all. Now uses 'cargo run' and proper crate dir structure, with a cargo.toml file.

* fixed up deletion to be more robust

* commented out debug message

* removed a bunch of unused and commented out code

* more cleanup, also -rm wasnt using the new snippet base dir function

* added a macro to wrap interactive commands, to warn and exit if not in a playground

* changed those big blocks of text to custom vars

* finally got the keymap working

* cleaned up the file header/template

* remembered that 'unless' exists

* killed dead code, added a comment

* Made template work in cargo.toml. Fixed places where 'unless doesnt work.

* fixed up the -rm function, now it actually kills all buffers related to the snippet (basically)

* corrected comment

* moved a function up for readability, updated Commentary documentation section, restored README.md, deleted unused upload/download code (rust playground on the web just uses gists on github)

* wasnt ever using the rust-playground-compile-command custom, so used that

* updated the startup screenshot to show the new stuff

* made use of some of the functions I defined, DRY

* fixed a hard coded path that was breaking the package

* used mapcar instead of seq-map because its built-in, made the snippet dir create parents for first run.

Author: jasonrobot

rust-playground.el

@@ -107,7 +107,7 @@ Start from PATH or the path of the current buffer's file, or NIL if this is not
   (if (not path)
       nil
     (if (not (string= path "/"))
-        (let ((base "/home/jason/.emacs.d/rust-playground")
+        (let ((base (expand-file-name rust-playground-basedir))
               (path-parent (file-name-directory (directory-file-name path))))
           (if (string= (file-name-as-directory base)
                        (file-name-as-directory path-parent))
@@ -141,7 +141,7 @@ Otherwise message the user that they aren't in one."
          (snippet-file-name (rust-playground-snippet-main-file-name snippet-dir))
          (snippet-cargo-toml (rust-playground-toml-file-name snippet-dir)))
     ;; create a buffer for Cargo.toml and switch to it
-    (make-directory snippet-dir)
+    (make-directory snippet-dir t)
     (set-buffer (create-file-buffer snippet-cargo-toml))
     (set-visited-file-name snippet-cargo-toml t)
     (rust-playground-mode)
@@ -194,7 +194,7 @@ Toggle between main.rs and Cargo.toml: C-c b
    (let* ((basedir (rust-playground-get-snippet-basedir))
           (srcdir (concat basedir (file-name-as-directory "src"))))
      ;; now get the fullpath of cargo.toml, and the fullpath of every file under src/
-     (remove 'nil (seq-map 'find-buffer-visiting
+     (remove 'nil (mapcar 'find-buffer-visiting
                            (cons (concat basedir "Cargo.toml")
                                  (directory-files srcdir t ".*\.rs")))))))