Fix travis and add network base_type (lsils#95)

* Ignore files.

* Travis.

* Network base_type.

* Docs.

.gitignore

@@ -1,8 +1,10 @@
 build/
 build-*/
 .vscode/
+examples/
 
 **/*~
+**/.DS_Store
 
 docs/_build
 docs/doxyxml

.travis.yml

@@ -50,18 +50,18 @@ matrix:
  before_install:
  - brew update
  - brew install llvm
- env: COMPILER=/usr/local/Cellar/llvm/7.0.0/bin/clang++
+ env: COMPILER=/usr/local/opt/llvm/bin/clang++
  - os: osx
  osx_image: xcode8.3
  compiler: gcc
  before_install:
  - brew update
  - brew install gcc
- env: COMPILER=/usr/local/Cellar/gcc/8.2.0/bin/g++-8
+ env: COMPILER=/usr/local/opt/gcc/bin/g++-8
  - os: osx
  osx_image: xcode8.3
  compiler: gcc
  before_install:
  - brew update
  - brew install gcc@7
- env: COMPILER=/usr/local/Cellar/gcc@7/7.3.0/bin/g++-7
+ env: COMPILER=/usr/local/opt/gcc@7/bin/g++-7

docs/network.rst

@@ -18,16 +18,16 @@ This page describes the interface of a logic network data structure in
 Mandatory types and constants
 -----------------------------
 
-The interaction with a logic network data structure is performed using three
-types for which no application details are assumed. The following three types
+The interaction with a logic network data structure is performed using four
+types for which no application details are assumed. The following four types
 must be defined within the network data structure. They can be implemented as
 nested type, but may also be exposed as type alias.
 
 .. doxygenclass:: mockturtle::network
- :members: node, signal, storage
+ :members: base_type, node, signal, storage
  :no-link:
 
-Futher, a network must expose the following compile-time constants:
+Further, a network must expose the following compile-time constants:
 
 .. code-block:: c++
 

docs/philosophy.rst

@@ -7,10 +7,10 @@ The *mockturtle* philosophy
 The mockturtle philosophy is based on a principle of 4 layers that depend on
 each other in a linear order as depicted in the figure on the right-hand side.
 The fundament, depicted by the bottom layer, is provided by the :ref:`network`.
-It defines naming conventions for types and methods for types and methods in
-classes that implement network interfaces, some of which are mandatory while
-others are optional. The network interface API does *not* provide any
-implementations for a network though.
+It defines naming conventions for types and methods in classes that implement
+network interfaces, some of which are mandatory while others are optional. The
+network interface API does *not* provide any implementations for a network
+though.
 
 Algorithms, the second layer, are implemented in terms of generic functions
 that takes as input an instance of some hypothetical network type and require

include/mockturtle/interface.hpp

@@ -46,6 +46,14 @@ static_assert( false, "file interface.hpp cannot be included, it's only used for
 class network final
 {
 public:
+ /*! \brief Type referring to itself.
+ *
+ * The ``base_type`` is the network type itself. It is required, because
+ * views may extend networks, and this type provides a way to determine the
+ * underlying network type.
+ */
+ using base_type = network;
+
  /*! \brief Type representing a node.
  *
  * A ``node`` is a node in the logic network. It could be a constant, a

include/mockturtle/networks/aig.hpp

@@ -90,6 +90,7 @@ class aig_network
  static constexpr auto min_fanin_size = 2u;
  static constexpr auto max_fanin_size = 2u;
 
+ using base_type = aig_network;
  using storage = std::shared_ptr<aig_storage>;
  using node = uint64_t;
 

include/mockturtle/networks/klut.hpp

@@ -75,6 +75,7 @@ class klut_network
  static constexpr auto min_fanin_size = 1;
  static constexpr auto max_fanin_size = 32;
 
+ using base_type = klut_network;
  using storage = std::shared_ptr<klut_storage>;
  using node = uint64_t;
  using signal = uint64_t;

include/mockturtle/networks/mig.hpp

@@ -68,6 +68,7 @@ class mig_network
  static constexpr auto min_fanin_size = 3u;
  static constexpr auto max_fanin_size = 3u;
 
+ using base_type = mig_network;
  using storage = std::shared_ptr<mig_storage>;
  using node = uint64_t;
 

include/mockturtle/networks/xag.hpp

@@ -89,6 +89,7 @@ class xag_network
  static constexpr auto min_fanin_size = 2u;
  static constexpr auto max_fanin_size = 2u;
 
+ using base_type = xag_network;
  using storage = std::shared_ptr<xag_storage>;
  using node = uint64_t;
 

include/mockturtle/networks/xmg.hpp

@@ -75,6 +75,7 @@ class xmg_network
  static constexpr auto min_fanin_size = 3u;
  static constexpr auto max_fanin_size = 3u;
 
+ using base_type = xmg_network;
  using storage = std::shared_ptr<xmg_storage>;
  using node = std::size_t;
 

include/mockturtle/traits.hpp

@@ -55,7 +55,8 @@ struct is_network_type : std::false_type
 template<class Ntk>
 struct is_network_type<Ntk, std::enable_if_t<
  std::is_constructible_v<signal<Ntk>, node<Ntk>>,
- std::void_t<signal<Ntk>,
+ std::void_t<typename Ntk::base_type,
+ signal<Ntk>,
  node<Ntk>,
  typename Ntk::storage,
  decltype( Ntk::max_fanin_size ),

test/test_networks.hpp

@@ -8,6 +8,7 @@ namespace mockturtle
 class dummy_network
 {
 public:
+ using base_type = dummy_network;
  using node = uint32_t;
  using signal = uint32_t;
  using storage = uint64_t;