no double streamer implementation, only use the python one

include/boost/histogram/axis.hpp

@@ -306,7 +306,12 @@ typedef variant<
   integer_axis
 > axis_type;
 
-std::ostream& operator<<(std::ostream&, const axis_type&);
+std::ostream& operator<<(std::ostream&, const regular_axis&);
+std::ostream& operator<<(std::ostream&, const polar_axis&);
+std::ostream& operator<<(std::ostream&, const variable_axis&);
+std::ostream& operator<<(std::ostream&, const category_axis&);
+std::ostream& operator<<(std::ostream&, const integer_axis&);
+// axis_type is automatically output-streamable if all its bounded types are 
 
 }
 }

src/axis.cpp

@@ -1,11 +1,28 @@
 #include <boost/histogram/axis.hpp>
 #include <limits>
 #include <sstream>
+#include <string>
 #include <stdexcept>
 
 namespace boost {
 namespace histogram {
 
+namespace {
+    std::string escape(const std::string& s) {
+        std::ostringstream os;
+        os << '\'';
+        for (unsigned i = 0; i < s.size(); ++i) {
+            const char c = s[i];
+            if (c == '\'' && (i == 0 || s[i - 1] != '\\'))
+                os << "\\\'";
+            else
+                os << c;
+        }
+        os << '\'';
+        return os.str();
+    }
+}
+
 axis_base::axis_base(int size,
                      const std::string& label,
                      bool uoflow) :
@@ -107,8 +124,9 @@ double
 polar_axis::operator[](int idx)
     const
 {
+    using namespace boost::math::double_constants;
     const double z = double(idx) / bins();
-    return z * 6.283185307179586 + start_;
+    return z * two_pi + start_;
 }
 
 bool
@@ -218,61 +236,57 @@ integer_axis::operator==(const integer_axis& o) const
            min_ == o.min_;
 }
 
-struct stream_visitor : public static_visitor<std::string>
+std::ostream& operator<<(std::ostream& os, const regular_axis& a)
 {
-    std::string operator()(const category_axis& a) const {
-        std::stringstream line;
-        line << "category_axis(";
-        for (int i = 0; i < a.bins(); ++i)
-            line << a[i] << (i == (a.bins() - 1)? ")" : ", ");
-        return line.str();
-    }
+    os << "regular_axis(" << a.bins() << ", " << a[0] << ", " << a[a.bins()];
+    if (!a.label().empty())
+        os << ", label=" << escape(a.label());
+    if (!a.uoflow())
+        os << ", uoflow=False";
+    os << ")";
+    return os;
+}
 
-    std::string operator()(const integer_axis& a) const {
-        std::stringstream line;
-        line << "integer_axis(";
-        if (a.bins())
-            line << a[0] << "," << a[a.bins() - 1];
-        line << ")";
-        return line.str();
-    }
+std::ostream& operator<<(std::ostream& os, const polar_axis& a)
+{
+    os << "polar_axis(" << a.bins();
+    if (a[0] != 0.0)
+        os << ", " << a[0];
+    if (!a.label().empty())
+        os << ", label=" << escape(a.label());
+    os << ")";
+    return os;
+}
 
-    std::string operator()(const polar_axis& a) const {
-        std::stringstream line;
-        line << "polar_axis(";
-        if (!a.label().empty())
-            line << a.label() << ", ";
-        line << a.bins() << ":";
-        for (int i = 0; i <= a.bins(); ++i)
-            line << " " << a.left(i);
-        return line.str();
-    }
+std::ostream& operator<<(std::ostream& os, const variable_axis& a)
+{
+    os << "variable_axis(" << a[0];
+    for (int i = 1; i <= a.bins(); ++i)
+        os << ", " << a.left(i);
+    if (!a.label().empty())
+        os << ", label=" << escape(a.label());
+    if (!a.uoflow())
+        os << ", uoflow=False";
+    os << ")";
+    return os;
+}
 
-    std::string operator()(const regular_axis& a) const {
-        std::stringstream line;
-        line << "regular_axis[";
-        if (!a.label().empty())
-            line << a.label() << ", ";
-        line << a.bins() << ":";
-        for (int i = 0; i <= a.bins(); ++i)
-            line << " " << a.left(i);
-        return line.str();
-    }
+std::ostream& operator<<(std::ostream& os, const integer_axis& a)
+{
+    os << "integer_axis(" << a[0] << ", " << a[a.bins() - 1];
+    if (!a.label().empty())
+        os << ", label=" << escape(a.label());
+    if (!a.uoflow())
+        os << ", uoflow=False";
+    os << ")";
+    return os;
+}
 
-    std::string operator()(const variable_axis& a) const {
-        std::stringstream line;
-        line << "variable_axis[";
-        if (!a.label().empty())
-            line << a.label() << ", ";
-        line << a.bins() << ":";
-        for (int i = 0; i <= a.bins(); ++i)
-            line << " " << a.left(i);
-        return line.str();
-    }
-};
-
-std::ostream& operator<<(std::ostream& os, const axis_type& a) {
-    os << apply_visitor(stream_visitor(), a);
+std::ostream& operator<<(std::ostream& os, const category_axis& a)
+{
+    os << "category_axis(";
+    for (int i = 0; i < a.bins(); ++i)
+        os << escape(a[i])  << (i == (a.bins() - 1)? ")" : ", ");
     return os;
 }
 

src/python/axis.cpp

@@ -112,6 +112,14 @@ axis_getitem(const T& t, int i) {
     return t[i];
 }
 
+template <typename T>
+std::string
+axis_repr(const T& t) {
+    std::ostringstream os;
+    os << t;
+    return os.str();
+}
+
 template<typename T>
 struct has_index_method
 {
@@ -123,74 +131,6 @@ struct has_index_method
     enum { value = sizeof(test<T>(0)) == sizeof(yes) };
 };
 
-std::string escape(const std::string& s) {
-    std::ostringstream os;
-    os << '\'';
-    for (unsigned i = 0; i < s.size(); ++i) {
-        const char c = s[i];
-        if (c == '\'' && (i == 0 || s[i - 1] != '\\'))
-            os << "\\\'";
-        else
-            os << c;
-    }
-    os << '\'';
-    return os.str();
-}
-
-std::string axis_repr(const regular_axis& a) {
-    std::stringstream s;
-    s << "regular_axis(" << a.bins() << ", " << a[0] << ", " << a[a.bins()];
-    if (!a.label().empty())
-        s << ", label=" << escape(a.label());
-    if (!a.uoflow())
-        s << ", uoflow=False";
-    s << ")";
-    return s.str();
-}
-
-std::string axis_repr(const polar_axis& a) {
-    std::stringstream s;
-    s << "polar_axis(" << a.bins();
-    if (a[0] != 0.0)
-        s << ", " << a[0];
-    if (!a.label().empty())
-        s << ", label=" << escape(a.label());
-    s << ")";
-    return s.str();
-}
-
-std::string axis_repr(const variable_axis& a) {
-    std::stringstream s;
-    s << "variable_axis(" << a[0];
-    for (int i = 1; i <= a.bins(); ++i)
-        s << ", " << a.left(i);
-    if (!a.label().empty())
-        s << ", label=" << escape(a.label());
-    if (!a.uoflow())
-        s << ", uoflow=False";
-    s << ")";
-    return s.str();
-}
-
-std::string axis_repr(const category_axis& a) {
-    std::stringstream s;
-    s << "category_axis(";
-    for (int i = 0; i < a.bins(); ++i)
-        s << escape(a[i])  << (i == (a.bins() - 1)? ")" : ", ");
-    return s.str();
-}
-
-std::string axis_repr(const integer_axis& a) {
-    std::stringstream s;
-    s << "integer_axis(" << a[0] << ", " << a[a.bins() - 1];
-    if (!a.label().empty())
-        s << ", label=" << escape(a.label());
-    if (!a.uoflow())
-        s << ", uoflow=False";
-    s << ")";
-    return s.str();
-}
-
 template <class T>
 struct axis_suite : public python::def_visitor<axis_suite<T> > {    
 
@@ -242,7 +182,7 @@ struct axis_suite : public python::def_visitor<axis_suite<T> > {
                    ":returns: category mapped to passed bin index" :
                    ":returns: low edge of the bin",
                python::args("self", "index"));
-        cl.def("__repr__", (std::string (*)(const T&)) &axis_repr,
+        cl.def("__repr__", axis_repr<T>,
                ":returns: string representation of this axis",
                python::arg("self"));
         cl.def(python::self == python::self);

test/axis_test.cpp

@@ -70,7 +70,7 @@ BOOST_AUTO_TEST_CASE(integer_axis_operators) {
     BOOST_CHECK_EQUAL(a, b);
 }
 
-BOOST_AUTO_TEST_CASE(stream_operator) {
+BOOST_AUTO_TEST_CASE(axis_type_streamable) {
     std::vector<double> x;
     x += -1, 0, 1;
     std::vector<axis_type> axes;