Use LCP to generate LogicalOperator boost serialization

Summary:
Since we are moving from boost to Capnp for serialization, it makes
sense to keep all of the LogicalOperator classes in LCP format. This
will make it easier to generate Capnp code.

Depends on D1361

Reviewers: buda, mferencevic, msantl, dgleich, ipaljak, mculinovic, mtomic

Reviewed By: mtomic

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D1362

.gitignore

@@ -37,3 +37,6 @@ TAGS
 # Cap'n Proto generated files
 *.capnp.c++
 *.capnp.h
+
+# LCP generated C++ files
+src/query/plan/operator.hpp

src/CMakeLists.txt

@@ -94,6 +94,8 @@ function(add_lcp lcp_file)
   set(generated_lcp_files ${generated_lcp_files} ${h_file} PARENT_SCOPE)
 endfunction(add_lcp)
 
+add_lcp(query/plan/operator.lcp)
+
 add_custom_target(generate_lcp DEPENDS ${generated_lcp_files})
 
 # Use this function to add each capnp file to generation. This way each file is

src/lisp/lcp.lisp

@@ -243,17 +243,18 @@
 (defun boost-serialization (cpp-class)
   "Add boost serialization code to `CPP-CLASS'."
   (labels ((get-serialize-code (member-name serialize-fun)
-             (make-raw-cpp
-              :string
              (if serialize-fun
-                  (etypecase serialize-fun
+                 ;; Invoke or use serialize-fun
-                    (string serialize-fun)
+                 (ctypecase serialize-fun
-                    (raw-cpp (raw-cpp-string serialize-fun))
+                   ((or string raw-cpp) serialize-fun)
                    (function
                     (let ((res (funcall serialize-fun "ar" member-name)))
                       (check-type res (or raw-cpp string))
                       res)))
-                  (format nil "ar & ~A;" member-name))))
+                 ;; Else use the default serialization
+                 #>cpp
+                 ar & ${member-name};
+                 cpp<#))
            (save-member (member)
              (get-serialize-code
               (cpp-member-name member :struct (cpp-class-structp cpp-class))

src/query/plan/operator.cpp

@@ -1604,10 +1604,6 @@ std::vector<Symbol> Produce::ModifiedSymbols(const SymbolTable &table) const {
   return OutputSymbols(table);
 }
 
-const std::vector<NamedExpression *> &Produce::named_expressions() {
-  return named_expressions_;
-}
-
 Produce::ProduceCursor::ProduceCursor(const Produce &self,
                                       database::GraphDbAccessor &db)
     : self_(self), db_(db), input_cursor_(self_.input_->MakeCursor(db)) {}