This Emacs library provides some basic methods for navigating and populating a c file buffer with project dependencies, e.g. #include and using namespace statements. Emphasis is on configuring to the project at hand with just Elisp, rather than relying on clang, or some other c project/file inference engine.

The list, cpp-dependencies should be set on a per project basis, and cpp-buf-utils provides a set of small dsl-like functions for creating it. As an example:

(setq cpp-dependencies
  (cpp-deps
   (dep "iostream" (include-bkt "iostream"))
   (dep "vector" (include-bkt "vector"))
   (dep "boost ns" nil (namespace "boost"))
   (dep
	 "boost program options"
	 (include-path "boost/program_options.hpp")
	 (namespaces
	   (namespace-alias "boost::program_options" "po")))
   (dep
	 "boost spirit"
	 (include-path "boost/spirit/include/qi.hpp")
	 (namespaces
	   (namespace-alias "boost::spirit::qi" "qi")))))

Legend

• dep "iostream", and dep "vector" define expansions for #include <iostream> and #include <vector> respectfully
• boost ns define a namespace expansion for a using namespace boost; expression.
• boost program options and boost spirit define a file includes, and a namespace alias for boost::program_options and boost::spirit::qi respectively.

As a side note, cpp-buf-deps also provides a list of common dependencies by default, see (std-cpp-deps) and (default-cpp-dependencies).

Then one can add members from this to the applicable section (e.g. #include section) by ido choice, with:

M-x cpp-dep-add 

Which results in the minibuffer options:

add c   dep: { iostream | vector | boost ns | boost program options | boost spirit } 

ido selecting iostream in this case results in #include <iostream> being included in the header section of the file. And similarly, selection of boost program options would insert both the include and namespace definition for that option.

A Note on how cpp-buf-utils searchers for addition points

cpp-buf-utils expects a #include section to already exist so it can find the insertion point, and similarly, a using declaration identifies the insertion point for namspaces. I'm considering adding a feature to use the cursor position when it is otherwise ambiguous.

M-x c-include-visit

To jump to the last #include <..> definition. And:

M-x c-include-unvisit

to return to the last cursor position.

(add-to-list 'load-path "~/path/to/cpp-buf-utils/")
(require 'cpp-buf-utils)