Merge pull request #308 from jcapriot/try_emplace

Switch to try_emplace

Author: jcapriot

discretize/_extensions/tree.cpp

@@ -137,31 +137,25 @@ Face::Face(Node& p1, Node& p2, Node& p3, Node& p4){
 Node * set_default_node(node_map_t& nodes, int_t x, int_t y, int_t z,
                         double *xs, double *ys, double *zs){
   int_t key = key_func(x, y, z);
-  Node * point;
-  if(nodes.count(key) == 0){
-    point = new Node(x, y, z, xs, ys, zs);
-    nodes[key] = point;
+  auto [it, inserted] = nodes.try_emplace(key, nullptr);
+  if(inserted){
+        // construct a new item at the emplaced location
+        it->second = new Node(x, y, z, xs, ys, zs);
   }
-  else{
-    point = nodes[key];
-  }
-  return point;
+  return it->second;
 }
 
 Edge * set_default_edge(edge_map_t& edges, Node& p1, Node& p2){
   int_t xC = (p1.location_ind[0]+p2.location_ind[0])/2;
   int_t yC = (p1.location_ind[1]+p2.location_ind[1])/2;
   int_t zC = (p1.location_ind[2]+p2.location_ind[2])/2;
   int_t key = key_func(xC, yC, zC);
-  Edge * edge;
-  if(edges.count(key) == 0){
-    edge = new Edge(p1, p2);
-    edges[key] = edge;
-  }
-  else{
-    edge = edges[key];
+  auto [it, inserted] = edges.try_emplace(key, nullptr);
+  if(inserted){
+        // construct a new item at the emplaced location
+        it->second = new Edge(p1, p2);
   }
-  return edge;
+  return it->second;
 };
 
 Face * set_default_face(face_map_t& faces, Node& p1, Node& p2, Node& p3, Node& p4){
@@ -170,15 +164,12 @@ Face * set_default_face(face_map_t& faces, Node& p1, Node& p2, Node& p3, Node& p
     y = (p1.location_ind[1]+p2.location_ind[1]+p3.location_ind[1]+p4.location_ind[1])/4;
     z = (p1.location_ind[2]+p2.location_ind[2]+p3.location_ind[2]+p4.location_ind[2])/4;
     key = key_func(x, y, z);
-    Face * face;
-    if(faces.count(key) == 0){
-        face = new Face(p1, p2, p3, p4);
-        faces[key] = face;
-    }
-    else{
-        face = faces[key];
+    auto [it, inserted] = faces.try_emplace(key, nullptr);
+    if(inserted){
+        // construct a new item at the emplaced location
+        it->second = new Face(p1, p2, p3, p4);
     }
-    return face;
+    return it->second;
 }
 
 Cell::Cell(Node *pts[8], int_t ndim, int_t maxlevel){

setup.py

@@ -75,6 +75,7 @@
     metadata["install_requires"] = install_requires
 else:
     from setuptools.extension import Extension
+    from setuptools.command.build_ext import build_ext
     from Cython.Build import cythonize
     import numpy as np
 
@@ -103,6 +104,26 @@
         ),
     ]
 
+    class build_ext_cpp_standard(build_ext):
+        # add compiler specific standard argument specifier
+        def build_extension(self, ext):
+            # This module requires c++17 standard
+            if ext.name == "discretize._extensions.tree_ext":
+                comp_type = self.compiler.compiler_type
+                if comp_type == "msvc":
+                    std_arg = "/std:c++17"
+                elif comp_type == "bcpp":
+                    raise Exception(
+                        "Must use cpp compiler that support C++17 standard."
+                    )
+                else:
+                    std_arg = "-std=c++17"
+                ext.extra_compile_args = [
+                    std_arg,
+                ]
+            super().build_extension(ext)
+
     metadata["ext_modules"] = cythonize(extensions)
+    metadata["cmdclass"] = {"build_ext": build_ext_cpp_standard}
 
 setup(**metadata)