Experiment with bazel

.gitignore

# ignore generated files

/bazel-bazel-test
/bazel-bin
/bazel-out
/bazel-testlogs
/WORKSPACE

BUILD

# BUILD

cc_binary(
    name = "powerset",
    srcs = ["powerset.cpp"],
    deps = ["@boost//:archive"]
)

powerset.cpp

/*
 * Copyright (c) 2013 Peter Simons <simons@cryp.to>
 *
 * This software is provided 'as-is', without any express or implied warranty.
 * In no event will the authors be held liable for any damages arising from the
 * use of this software.
 *
 * Copying and distribution of this file, with or without modification, are
 * permitted in any medium without royalty provided the copyright notice and
 * this notice are preserved.
 */

#include <iostream>
#include <boost/array.hpp>
#include <boost/assert.hpp>
#include <boost/cstdint.hpp>

namespace boost
{
  template <class T, std::size_t N>
  inline std::ostream & operator<< (std::ostream & os, boost::array<T, N> const & arr)
  {
    std::copy(arr.begin(), arr.end(), std::ostream_iterator<T>(os, " "));
    return os;
  }
}

template <class IteratorType, class SizeType = uintmax_t>
class powerset
{
public:
  typedef IteratorType iterator;
  typedef SizeType size_type;

  powerset(iterator const & begin, iterator const & end) : _begin(begin), _end(end), _max_state(1u << std::distance(begin, end)), _state(0u)
  {
    BOOST_ASSERT(_max_state >= 0);
  }

  size_type size() const { _max_state; }

  bool more() const { return _state < _max_state; }
  bool empty() const { return _state == _max_state; }

  template <class OutputIterator>
  void write_to(OutputIterator oi)
  {
    iterator i(_begin);
    for (size_type state(_state); state != 0; state>>=1, ++i)
    {
      if (state & 1) *oi++ = *i;
    }
  }

  void next() { ++_state; }

private:
  iterator _begin, _end;
  size_type _max_state;
  size_type _state;
};

int main(int, char * [])
{
  typedef char value_type;
  typedef boost::array<value_type, 5u> array_type;
  typedef powerset<array_type::const_iterator> powerset_type;
  array_type const arr = {{ 'a', 'b', 'c', 'd', 'e' }};
  for (powerset_type pset(arr.begin(), arr.end()); pset.more(); pset.next())
  {
    pset.write_to(std::ostream_iterator<value_type>(std::cout, " "));
    std::cout << std::endl;
  }
  return 0;
}

WORKSPACE.inpure

# WORKSPACE
#
# Based on code posted in https://github.com/bazelbuild/bazel/issues/8846.
#

new_local_repository(
    name = "boost",
    path = "/usr/include",
    build_file_content = """
package(default_visibility = ["//visibility:public"])
cc_library(
    name = "devel",
    hdrs = glob(["boost/**/*.hpp"])
)
"""
)

WORKSPACE.pure

# WORKSPACE

load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")

git_repository(
    name = "com_github_nelhage_rules_boost",
    commit = "9f9fb8b2f0213989247c9d5c0e814a8451d18d7f",
    remote = "https://github.com/nelhage/rules_boost",
    shallow_since = "1570056263 -0700",
)

load("@com_github_nelhage_rules_boost//:boost/boost.bzl", "boost_deps")
boost_deps()