bug#27230: eldoc doc

[Eli Zaretskii]

> From: "Charles A. Roelli" <charles@aurox.ch>
> Date: Sun, 25 Jun 2017 11:14:23 +0200
> 
> Here's a doc patch for ElDoc, with some minor readability fixes.

Thanks.  Please allow me a few comments below.

> -(defun eldoc-message (&rest args)
> +(defun eldoc-message (&optional format-string &rest args)
> +  "Store and display the given message.

The first line of a doc string should ideally mention the arguments.

> +FORMAT-STRING and ARGS, if given, are passed to `format-message',
> +the output of which is stored in `eldoc-last-message'.

This leaves me wondering what happens if no arguments are supplied.

>  (defun eldoc--message-command-p (command)
> +  "Non-nil if COMMAND is a command in `eldoc-message-commands'."

"Return non-nil if ...".  The way you wrote it is appropriate for a
variable, not for a function.

>  (defun eldoc-pre-command-refresh-echo-area ()
> +  "Reprint `eldoc-last-message' to the echo area."

Are you sure about the "to" part?  I'd say "in" sounds more correct.

>  (defun eldoc-display-message-p ()
> +  "Non-nil when appropriate to display an ElDoc message."

"Return non-nil"

>  (defun eldoc-display-message-no-interference-p ()
> +  "Nil when displaying an ElDoc message would cause interference
> +with other features."

Likewise.  Also, the first line of a doc string should be a complete
sentence.

>  (defun eldoc-print-current-symbol-info ()
> +  "Print the output of `eldoc-documentation-function'."

"Print the output" sounds confusing.  How about this instead:

  Print the text produced by `eldoc-documentation-function'.

>  (defun eldoc-docstring-format-sym-doc (prefix doc &optional face)
> +  "Concatenate PREFIX and DOC, returning the largest part of the
> +resultant string that can fit in the minibuffer window.

First line not a complete sentence again.

> +When PREFIX is a symbol, apply FACE to it before concatenating.

But FACE is optional, so what if it isn't given?

Thanks for working on this.