Simplify import_numpy

Author: SylvainCorlay

include/xtensor-python/pycontainer.hpp

@@ -19,7 +19,6 @@
 
 #ifndef FORCE_IMPORT_ARRAY
 #define NO_IMPORT_ARRAY
-static int _import_array() { return 0; };
 #endif
 #ifndef PY_ARRAY_UNIQUE_SYMBOL
 #define PY_ARRAY_UNIQUE_SYMBOL xtensor_python_ARRAY_API
@@ -33,17 +32,7 @@ static int _import_array() { return 0; };
 namespace xt
 {
 
-    /**
-     * Import the numpy Python module.
-     */
-    inline void import_numpy()
-    {
-        if (_import_array() < 0)
-        {
-            PyErr_Print();
-            PyErr_SetString(PyExc_ImportError, "numpy.core.multiarray failed to import");
-        }
-    }
+    inline void import_numpy();
 
     /**
      * @class pycontainer
@@ -253,6 +242,19 @@ namespace xt
         *static_cast<derived_type*>(this) = std::move(tmp);
     }
 
+    /**
+     * Import the numpy Python module.
+     */
+    inline void import_numpy()
+    {
+        #ifdef FORCE_IMPORT_ARRAY
+        if (_import_array() < 0)
+        {
+            PyErr_Print();
+            PyErr_SetString(PyExc_ImportError, "numpy.core.multiarray failed to import");
+        }
+        #endif
+    }
 }
 
 #endif