mark constructors in Function*<dim> as explicit

While not strictly backwards compatible, I think it is a very dangerous
design to have things convert to Function<dim> automatically including
an int. Stop this by marking them explicit.

diff --git a/include/deal.II/base/function.h b/include/deal.II/base/function.h
index 3fed52cf6bd187e1eb19c97e54ea419c3ca96c13..3ea52c8b08509e4f9db412c91beb0e4a94057f14 100644 (file)
--- a/include/deal.II/base/function.h
+++ b/include/deal.II/base/function.h
@@ -174,8 +174,8 @@ public:
    * (which defaults to one, i.e. a scalar function), and the time variable,
    * which defaults to zero.
    */
-  Function(const unsigned int n_components = 1,
-           const time_type    initial_time = 0.0);
+  explicit Function(const unsigned int n_components = 1,
+                    const time_type    initial_time = 0.0);
 
   /**
    * Copy constructor.
@@ -414,22 +414,22 @@ namespace Functions
      * Constructor; set values of all components to the provided one. The
      * default number of components is one.
      */
-    ConstantFunction(const RangeNumberType value,
-                     const unsigned int    n_components = 1);
+    explicit ConstantFunction(const RangeNumberType value,
+                              const unsigned int    n_components = 1);
 
     /**
      * Constructor; takes an <tt>std::vector<RangeNumberType></tt> object as an
      * argument. The number of components is determined by
      * <tt>values.size()</tt>.
      */
-    ConstantFunction(const std::vector<RangeNumberType> &values);
+    explicit ConstantFunction(const std::vector<RangeNumberType> &values);
 
     /**
      * Constructor; takes an <tt>Vector<RangeNumberType></tt> object as an
      * argument. The number of components is determined by
      * <tt>values.size()</tt>.
      */
-    ConstantFunction(const Vector<RangeNumberType> &values);
+    explicit ConstantFunction(const Vector<RangeNumberType> &values);
 
     /**
      * Constructor; uses whatever stores in [begin_ptr, begin_ptr+n_components)
@@ -513,7 +513,7 @@ namespace Functions
     /**
      * Constructor. The number of components is preset to one.
      */
-    ZeroFunction(const unsigned int n_components = 1);
+    explicit ZeroFunction(const unsigned int n_components = 1);
   };
 
 } // namespace Functions
@@ -709,7 +709,7 @@ public:
    * value, convert this into an object that matches the Function<dim,
    * RangeNumberType> interface.
    */
-  ScalarFunctionFromFunctionObject(
+  explicit ScalarFunctionFromFunctionObject(
     const std::function<RangeNumberType(const Point<dim> &)> &function_object);
 
   /**
@@ -878,7 +878,7 @@ public:
    * method will trigger an exception, unless you first call the
    * set_function_gradients() method.
    */
-  FunctionFromFunctionObjects(
+  explicit FunctionFromFunctionObjects(
     const std::vector<std::function<RangeNumberType(const Point<dim> &)>>
       &          values,
     const double initial_time = 0.0);
@@ -1011,7 +1011,7 @@ public:
    * the first argument.  This should be such that the entire tensor_function
    * fits inside the <tt>n_component</tt> length return vector.
    */
-  VectorFunctionFromTensorFunction(
+  explicit VectorFunctionFromTensorFunction(
     const TensorFunction<1, dim, RangeNumberType> &tensor_function,
     const unsigned int                             selected_component = 0,
     const unsigned int                             n_components       = dim);