Automatic to_<tag> Python method. (#9)

Author: msoeken

docs/changelog.rst

@@ -1,8 +1,8 @@
 Change Log
 ==========
 
-v0.3 (not yet released)
------------------------
+v0.3 (July 22, 2018)
+--------------------
 
 * Throw and catch errors in `read`.
 
@@ -18,6 +18,9 @@ v0.3 (not yet released)
 * General commands: ``store --pop`` to remove current store element
   `#8 <https://github.com/msoeken/alice/pull/8>`_
 
+* Automatic ``to_<tag>`` in Python interface as shortcut for ``write_<tag>(log=True)["contents"]``
+  `#9 <https://github.com/msoeken/alice/pull/9>`_
+
 v0.2 (May 7, 2018)
 ------------------
 

include/alice/api.hpp

@@ -164,6 +164,37 @@ struct insert_write_commands<CLI, Tuple, 0>
   }
 };
 
+#if defined ALICE_PYTHON
+template<typename CLI, typename Tuple, std::size_t Index>
+struct make_special_write_commands
+{
+  make_special_write_commands( CLI& cli, py::module& m )
+  {
+    make_special_write_commands<CLI, Tuple, Index - 1> irc( cli, m );
+
+    using tag_type = std::tuple_element_t<Index - 1, Tuple>;
+    //cli.template insert_write_command<tag_type>( fmt::format( "write_{}", alice_globals::get().write_tags[Index - 1] ), alice_globals::get().write_names[Index - 1] );
+    
+    auto const& tag = alice_globals::get().write_tags[Index - 1];
+    const auto name = fmt::format( "write_{}", tag );
+    auto const& cmd = cli.env->commands().at( name );
+    m.def( fmt::format( "to_{}", tag ).c_str(), [cmd, name]( py::kwargs kwargs ) -> py::str {
+      auto pargs = detail::make_args( name, kwargs );
+      pargs.push_back( "--log" );
+      cmd->run( pargs );
+      const auto log = cmd->log();
+      return py::str( log["contents"].template get<std::string>() );
+    } );
+  }
+};
+
+template<typename CLI, typename Tuple>
+struct make_special_write_commands<CLI, Tuple, 0>
+{
+  make_special_write_commands( CLI& cli, py::module& m ) {}
+};
+#endif
+
 /*! \brief Returns a one-line string to show when printing store contents
 
   This macro is used to return a string that is shown in the output of
@@ -501,6 +532,7 @@ PYBIND11_MODULE(prefix, m) \
 { \
   _ALICE_MAIN_BODY(prefix) \
   alice::detail::create_python_module( cli, m ); \
+  make_special_write_commands<cli_t, alice_write_tags, std::tuple_size<alice_write_tags>::value> swc( cli, m ); \
 }
 #elif defined ALICE_CINTERFACE
 #define ALICE_MAIN(prefix) \

include/alice/detail/python.hpp

@@ -172,6 +172,39 @@ class return_value_dict
   std::string repr_html;
 };
 
+inline std::vector<std::string> make_args( const std::string& name, py::kwargs kwargs )
+{
+  std::vector<std::string> pargs = {name};
+
+  for ( const auto& kp : kwargs )
+  {
+    // get the key as string
+    const auto skey = kp.first.cast<std::string>();
+    const auto value = kp.second;
+
+    // TODO cast float to string?
+    if ( py::isinstance<py::bool_>( value ) )
+    {
+      if ( value.cast<bool>() )
+      {
+        pargs.push_back( "--" + skey );
+      }
+    }
+    else if ( py::isinstance<py::int_>( value ) )
+    {
+      pargs.push_back( "--" + skey );
+      pargs.push_back( std::to_string( value.cast<int>() ) );
+    }
+    else
+    {
+      pargs.push_back( "--" + skey );
+      pargs.push_back( value.cast<std::string>() );
+    }
+  }
+
+  return pargs;
+}
+
 template<typename CLI>
 void create_python_module( CLI& cli, py::module& m )
 {
@@ -187,34 +220,7 @@ void create_python_module( CLI& cli, py::module& m )
   for ( const auto& p : cli.env->commands() )
   {
     m.def( p.first.c_str(), [p]( py::kwargs kwargs ) -> py::object {
-      std::vector<std::string> pargs = {p.first};
-
-      for ( const auto& kp : kwargs )
-      {
-        // get the key as string
-        const auto skey = kp.first.cast<std::string>();
-        const auto value = kp.second;
-
-        // TODO cast float to string?
-        if ( py::isinstance<py::bool_>( value ) )
-        {
-          if ( value.cast<bool>() )
-          {
-            pargs.push_back( "--" + skey );
-          }
-        }
-        else if ( py::isinstance<py::int_>( value ) )
-        {
-          pargs.push_back( "--" + skey );
-          pargs.push_back( std::to_string( value.cast<int>() ) );
-        }
-        else
-        {
-          pargs.push_back( "--" + skey );
-          pargs.push_back( value.cast<std::string>() );
-        }
-      }
-      p.second->run( pargs );
+      p.second->run( make_args( p.first, kwargs ) );
 
       const auto log = p.second->log();