Function: package-install

package-install is an autoloaded, interactive and byte-compiled function defined in package.el.gz.

Signature

(package-install PKG &optional DONT-SELECT)

Documentation

Install the package PKG.

PKG can be a package-desc or a symbol naming one of the available packages in an archive in package-archives. When called interactively, prompt for the package name.

Mark the installed package as selected by adding it to package-selected-packages.

When called from Lisp and optional argument DONT-SELECT is non-nil, install the package but do not add it to package-selected-packages.

If PKG is a package-desc and it is already installed, don't try to install it but still mark it as selected.

Probably introduced at or before Emacs version 25.1.

Key Bindings

Source Code

;; Defined in /usr/src/emacs/lisp/emacs-lisp/package.el.gz
;;;###autoload
(defun package-install (pkg &optional dont-select)
  "Install the package PKG.
PKG can be a `package-desc' or a symbol naming one of the
available packages in an archive in `package-archives'.  When
called interactively, prompt for the package name.

Mark the installed package as selected by adding it to
`package-selected-packages'.

When called from Lisp and optional argument DONT-SELECT is
non-nil, install the package but do not add it to
`package-selected-packages'.

If PKG is a `package-desc' and it is already installed, don't try
to install it but still mark it as selected."
  (interactive
   (progn
     ;; Initialize the package system to get the list of package
     ;; symbols for completion.
     (package--archives-initialize)
     (list (intern (completing-read
                    "Install package: "
                    (delq nil
                          (mapcar (lambda (elt)
                                    (unless (package-installed-p (car elt))
                                      (symbol-name (car elt))))
                                  package-archive-contents))
                    nil t))
           nil)))
  (package--archives-initialize)
  (add-hook 'post-command-hook #'package-menu--post-refresh)
  (let ((name (if (package-desc-p pkg)
                  (package-desc-name pkg)
                pkg)))
    (unless (or dont-select (package--user-selected-p name))
      (package--save-selected-packages
       (cons name package-selected-packages)))
    (if-let* ((transaction
               (if (package-desc-p pkg)
                   (unless (package-installed-p pkg)
                     (package-compute-transaction (list pkg)
                                                  (package-desc-reqs pkg)))
                 (package-compute-transaction () (list (list pkg))))))
        (progn
          (package-download-transaction transaction)
          (package--quickstart-maybe-refresh)
          (message  "Package `%s' installed." name))
      (message "`%s' is already installed" name))))