[RFA,1/5] Add class scoped_switch_auto_to_sym_language.

The class scoped_switch_auto_to_sym_language allows to switch in a scope
the current language to the language of a symbol when language mode is
set to auto.

2018-10-27  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* language.h (scoped_switch_auto_to_sym_language): new class.
---
 gdb/language.h | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

On 10/28/2018 02:46 PM, Philippe Waroquiers wrote:
> The class scoped_switch_auto_to_sym_language allows to switch in a scope
> the current language to the language of a symbol when language mode is
> set to auto.
> 
> 2018-10-27  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
> 
> 	* language.h (scoped_switch_auto_to_sym_language): new class.

s/new/New/

> ---
>  gdb/language.h | 39 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/gdb/language.h b/gdb/language.h
> index 02a84ff9a2..47a88de756 100644
> --- a/gdb/language.h
> +++ b/gdb/language.h
> @@ -707,4 +707,43 @@ private:
>    enum language m_lang;
>  };
>  
> +/* If language_mode is language_mode_auto,
> +   then switches current language to the language of SYM
> +   and restore current language upon destruction.
> +
> +   Else does nothing.  */

Either
   s/switches/switch/
   s/does/do/
or
   s/restore/restores/

I'd go with the former.

> +
> +class scoped_switch_auto_to_sym_language

I have to admit that I had trouble grokking the class's name
for a bit.  I don't have a much better suggestion, though
this would read a bit better to me:

         scoped_switch_to_sym_language_if_auto
         scoped_switch_to_sym_lang_if_auto

But may well be just me.  Feel free to ignore.

> +{
> +public:
> +
> +  explicit scoped_switch_auto_to_sym_language (const struct symbol *sym)
> +  {
> +    if (language_mode == language_mode_auto)
> +      {
> +	m_lang = current_language->la_language;
> +	m_switched = true;
> +	set_language (SYMBOL_LANGUAGE (sym));
> +      }
> +    else
> +      m_switched = false;
> +  }
> +
> +  ~scoped_switch_auto_to_sym_language ()
> +  {
> +    if (m_switched)
> +      set_language (m_lang);
> +  }
> +
> +  scoped_switch_auto_to_sym_language
> +      (const scoped_switch_auto_to_sym_language &)
> +      = delete;
> +  scoped_switch_auto_to_sym_language &operator=
> +      (const scoped_switch_auto_to_sym_language &) = delete;

Use DISABLE_COPY_AND_ASSIGN instead.

Otherwise OK.

> +
> +private:
> +  bool m_switched;
> +  enum language m_lang;
> +};
> +
>  #endif /* defined (LANGUAGE_H) */
> 

Thanks,
Pedro Alves