[patch] [python] Prompt substitution

[Eli Zaretskii]

> From: Phil Muldoon <pmuldoon@redhat.com>
> Date: Mon, 18 Jul 2011 16:45:51 +0100
> 
> 2011-07-18  Phil Muldoon  <pmuldoon@redhat.com>
> 
> 	* observer.texi (GDB Observers): Add before_prompt observer.
> 	* gdb.texinfo (Basic Python): Add documentation for setting,
> 	getting and prompt substitution.

Thanks.

> +@defun set_current_prompt @r{[}new_prompt@r{]}
> +Sets the @value{GDBN} prompt to @var{new_prompt}.
   ^^^^
"Set", not "sets", to be consistent with the way we describe other
methods.

You don't say what is the effect of omitting new_prompt (which is
optional, according to the "[...]" syntax).

> +@defop Operation {@value{GDBN}} prompt_hook [current_prompt]
                                               ^^^^^^^^^^^^^^^^
You need @r{} here as well.

Also, what happens if current_prompt is omitted?

> +Called before a top-level prompt is displayed. @var{current_prompt} is
                                                ^^
Two spaces, please.

The documentation parts are okay with these comments.