Prerequisites:
To use ya-cppref.el, you need to have w3m and emacs-w3m installed in
your system.  You need also to get cppreference.com reference,
inflating it, and put it in your system.  The document of
cppreference.com is available on
http://en.cppreference.com/w/Cppreference:Archives

Installation:
Put ya-cppref.el in the directory which is included in load path, and
add the following to your emacs setting file:
(require 'ya-cppref)

Also you need to specify the root directory of documents in your
emacs setting file.
The below is a few examples.
If you place the documents in /usr/local/doc/cpp, then
(setq ya-cppref-path-to-doc-root "/usr/local/doc/cpp/reference/")

If you place the documents in ~/doc/cppreference, then
(setq ya-cppref-path-to-doc-root "~/doc/cppreference/reference/")

Please note that the path should end with `/', and the reference
directory above is the root direcotry in the zip file.

Usage scenario:
* Searching for the doc about vector::push_back
M-x ya-cppref [RET]
ya-cppref: push_back [RET]    ; type push_back
`push_back' in: vector [RET]  ; choose class.

* Searching for the doc about list
M-x ya-cppref [RET]
ya-cppref: list [RET]         ; type list
`list' in: container [RET]    ; choose container

Note that when you type function names or class names, completion
is available.

I hope this will help. Thanks.