Update kernel constructors

Author: anutosh491

include/xeus-cpp/xinterpreter_wasm.hpp

@@ -19,7 +19,7 @@ namespace xcpp
     {
     public:
 
-        wasm_interpreter(const std::vector<std::string>& args);
+        wasm_interpreter(int argc = 0, char** argv = nullptr);
         virtual ~wasm_interpreter() = default;
 
     };

include/xeus-cpp/xutils.hpp

@@ -32,9 +32,6 @@ namespace xcpp
 
     XEUS_CPP_API
     std::string retrieve_tagfile_dir();
-
-    XEUS_CPP_API
-    std::pair<int, char**> convert_to_argv(const std::vector<std::string>& args);
 }
 
 #endif

src/main_emscripten_kernel.cpp

@@ -15,9 +15,26 @@
 
 #include "xeus-cpp/xinterpreter_wasm.hpp"
 
+template <class interpreter_type>
+interpreter_type* builder_with_args(emscripten::val js_args)
+{
+    static std::vector<std::string> args = emscripten::vecFromJSArray<std::string>(js_args);
+    static std::vector<const char*> argv_vec;
+
+    for (const auto& s : args)
+    {
+        argv_vec.push_back(s.c_str());
+    }
+
+    int argc = static_cast<int>(argv_vec.size());
+    char** argv = const_cast<char**>(argv_vec.data());
+
+    return new interpreter_type(argc, argv);
+}
+
 EMSCRIPTEN_BINDINGS(my_module)
 {
     xeus::export_core();
     using interpreter_type = xcpp::wasm_interpreter;
-    xeus::export_kernel<interpreter_type>("xkernel");
+    xeus::export_kernel<interpreter_type, &builder_with_args<interpreter_type>>("xkernel");
 }

src/xinterpreter_wasm.cpp

@@ -12,11 +12,11 @@
 
 #include "xeus-cpp/xinterpreter.hpp"
 #include "xeus-cpp/xinterpreter_wasm.hpp"
-#include "xeus-cpp/xutils.hpp"
 
 namespace xcpp
 {
-    wasm_interpreter::wasm_interpreter(const std::vector<std::string>& args)
-        : interpreter(convert_to_argv(args).first, convert_to_argv(args).second)
-    {}
+    wasm_interpreter::wasm_interpreter(int argc, char** argv)
+        : interpreter(argc, argv)
+    {
+    }
 }

src/xutils.cpp

@@ -102,21 +102,4 @@ namespace xcpp
 
         return prefix + "share" + separator + "xeus-cpp" + separator + "tagfiles";
     }
-
-    std::pair<int, char**> convert_to_argv(const std::vector<std::string>& args)
-    {
-        static std::vector<std::string> persistent_args = args;
-        static std::vector<const char*> argv_vec;
-
-        argv_vec.clear();
-        for (const auto& s : persistent_args)
-        {
-            argv_vec.push_back(s.c_str());
-        }
-
-        return {
-            static_cast<int>(argv_vec.size()),
-            const_cast<char**>(argv_vec.data())
-        };
-    }
 }