partial lambda support

include/mstch/mstch.hpp

@@ -4,12 +4,26 @@
 #include <vector>
 #include <map>
 #include <string>
+#include <functional>
 
 #include <boost/variant.hpp>
 
 namespace mstch {
+    // booleans must be wrapped, because std::function is implicitly convertible
+    // to a bool.
+    class boolean {
+    private:
+        bool state;
+    public:
+        boolean(bool b): state(b) {}
+        operator bool() const { return state; }
+    };
+
+    using renderer = std::function<std::string(const std::string&)>;
+    using string_lambda = std::function<std::string()>;
+    using renderer_lambda = std::function<std::function<std::string(const std::string&,renderer)>()>;
     using node = boost::make_recursive_variant<
-            boost::blank, std::string, int, bool,
+            boost::blank, std::string, int, boolean, string_lambda, renderer_lambda,
             std::map<const std::string,boost::recursive_variant_>,
             std::vector<boost::recursive_variant_>>::type;
     using object = std::map<const std::string,node>;

src/visitor/is_node_empty.cpp

@@ -25,3 +25,11 @@ bool visitor::is_node_empty::operator()(const array& arr) const {
 bool visitor::is_node_empty::operator()(const object& obj) const {
     return false;
 }
+
+bool visitor::is_node_empty::operator()(const string_lambda& lambda) const {
+    return false; // TODO
+}
+
+bool visitor::is_node_empty::operator()(const renderer_lambda& lambda) const {
+    return false; // TODO
+}

src/visitor/is_node_empty.hpp

@@ -16,6 +16,8 @@ namespace mstch {
             bool operator()(const std::string& str) const;
             bool operator()(const array& arr) const;
             bool operator()(const object& obj) const;
+            bool operator()(const string_lambda& lambda) const;
+            bool operator()(const renderer_lambda& lambda) const;
         };
     }
 }

src/visitor/render_node.cpp

@@ -31,3 +31,17 @@ std::string visitor::render_node::operator()(const array& arr) const {
 std::string visitor::render_node::operator()(const object& obj) const {
     return "";
 }
+
+std::string visitor::render_node::operator()(
+        const string_lambda& lambda) const
+{
+    return this->operator()(lambda());
+}
+
+std::string visitor::render_node::operator()(
+        const renderer_lambda& lambda) const
+{
+    return this->operator()((lambda())("", [](const std::string& text) {
+        return std::string{""};
+    }));
+}

src/visitor/render_node.hpp

@@ -22,6 +22,8 @@ namespace mstch {
             std::string operator()(const std::string& str) const;
             std::string operator()(const array& arr) const;
             std::string operator()(const object& obj) const;
+            std::string operator()(const string_lambda& lambda) const;
+            std::string operator()(const renderer_lambda& lambda) const;
         };
     }
 }

src/visitor/render_section.cpp

@@ -46,3 +46,17 @@ std::string visitor::render_section::operator()(const array& a) const {
                     render_section(context, section, {flag::keep_array}), item);
     return out.str();
 }
+
+std::string visitor::render_section::operator()(
+        const string_lambda& lambda) const
+{
+    return lambda();
+}
+
+std::string visitor::render_section::operator()(
+        const renderer_lambda& lambda) const
+{
+    return (lambda())(section, [&](const std::string& text) {
+        return render_context(mstch::object{}, context).render(text);
+    });
+}

src/visitor/render_section.hpp

@@ -28,6 +28,8 @@ namespace mstch {
             std::string operator()(const std::string& str) const;
             std::string operator()(const array& arr) const;
             std::string operator()(const object& obj) const;
+            std::string operator()(const string_lambda& lambda) const;
+            std::string operator()(const renderer_lambda& lambda) const;
         };
     }
 }

src/visitor/to_json.cpp

@@ -41,3 +41,11 @@ std::string visitor::to_json::operator()(const object& obj) const {
     out << "}";
     return out.str();
 }
+
+std::string visitor::to_json::operator()(const string_lambda& lambda) const {
+    return ""; // TODO
+}
+
+std::string visitor::to_json::operator()(const renderer_lambda& lambda) const {
+    return ""; // TODO
+}

src/visitor/to_json.hpp

@@ -17,6 +17,8 @@ namespace mstch {
             std::string operator()(const std::string& str) const;
             std::string operator()(const array& arr) const;
             std::string operator()(const object& obj) const;
+            std::string operator()(const string_lambda& lambda) const;
+            std::string operator()(const renderer_lambda& lambda) const;
         };
     }
 }

test/data/comments.data

@@ -0,0 +1,5 @@
+mstch::object{
+  {"title", []() {
+    return std::string{"A Comedy of Errors"};
+  }}
+};

test/data/escaped.data

@@ -0,0 +1,6 @@
+mstch::object{
+  {"title", []() {
+    return "Bear > Shark";
+  }},
+  {"entities", std::string{"&quot; \"'<>/"}}
+}

test/data/lambda/comments.js

@@ -1,5 +0,0 @@
-({
-  title: function () {
-    return "A Comedy of Errors";
-  }
-})

test/data/lambda/escaped.js

@@ -1,6 +0,0 @@
-({
-  title: function () {
-    return "Bear > Shark";
-  },
-  entities: "&quot; \"'<>/"
-})

test/data/lambda/nested_higher_order_sections.js

@@ -1,8 +0,0 @@
-({
-  bold: function () {
-    return function (text, render) {
-      return '<b>' + render(text) + '</b>';
-    };
-  },
-  person: { name: 'Jonas' }
-});

test/data/lambda/partial_template.js

@@ -1,6 +0,0 @@
-({
-  title: function () {
-    return "Welcome";
-  },
-  again: "Goodbye"
-})

test/data/lambda/section_functions_in_partials.js

@@ -1,7 +0,0 @@
-({
-  bold: function(){
-    return function(text, render) {
-      return "<b>" + render(text) + "</b>";
-    }
-  }
-})

test/data/lambda/unescaped.js

@@ -1,5 +0,0 @@
-({
-  title: function () {
-    return "Bear > Shark";
-  }
-})

test/data/nested_higher_order_sections.data

@@ -0,0 +1,8 @@
+mstch::object{
+  {"bold", []() {
+    return [](const std::string& text, mstch::renderer render) {
+      return std::string{"<b>"} + render(text) + std::string{"</b>"};
+    };
+  }},
+  {"person", mstch::object{{"name", std::string{"Jonas"}}}}
+}

test/data/partial_template.data

@@ -0,0 +1,6 @@
+mstch::object{
+  {"title", []() {
+    return std::string{"Welcome"};
+  }},
+  {"again", std::string{"Goodbye"}}
+}

test/data/section_functions_in_partials.data

@@ -0,0 +1,7 @@
+mstch::object{
+  {"bold", []() {
+    return [](const std::string& text, mstch::renderer render) {
+      return std::string{"<b>"} + render(text) + std::string{"</b>"};
+    };
+  }}
+}

test/data/unescaped.data

@@ -0,0 +1,5 @@
+mstch::object{
+  {"title", [](){
+    return std::string{"Bear > Shark"};
+  }}
+}

test/test_main.cpp

@@ -20,6 +20,7 @@ MSTCH_TEST(array_of_strings)
 MSTCH_TEST(backslashes)
 MSTCH_TEST(bug_11_eating_whitespace)
 MSTCH_TEST(bug_length_property)
+MSTCH_TEST(comments)
 MSTCH_TEST(context_lookup)
 MSTCH_TEST(disappearing_whitespace)
 MSTCH_TEST(double_render)
@@ -28,6 +29,7 @@ MSTCH_TEST(empty_sections)
 MSTCH_TEST(empty_string)
 MSTCH_TEST(empty_template)
 MSTCH_TEST(error_not_found)
+MSTCH_TEST(escaped)
 MSTCH_TEST(falsy)
 MSTCH_TEST(falsy_array)
 MSTCH_TEST(grandparent_context)
@@ -37,6 +39,7 @@ MSTCH_TEST(inverted_section)
 MSTCH_TEST(keys_with_questionmarks)
 MSTCH_TEST(multiline_comment)
 MSTCH_TEST(nested_dot)
+MSTCH_TEST(nested_higher_order_sections)
 MSTCH_TEST(nested_iterating)
 MSTCH_TEST(nesting)
 MSTCH_TEST(nesting_same_name)
@@ -47,11 +50,14 @@ MSTCH_PARTIAL_TEST(partial_array)
 MSTCH_PARTIAL_TEST(partial_array_of_partials)
 MSTCH_PARTIAL_TEST(partial_array_of_partials_implicit)
 MSTCH_PARTIAL_TEST(partial_empty)
+MSTCH_PARTIAL_TEST(partial_template)
 MSTCH_TEST(recursion_with_same_names)
 MSTCH_TEST(reuse_of_enumerables)
 MSTCH_TEST(section_as_context)
+MSTCH_PARTIAL_TEST(section_functions_in_partials)
 MSTCH_TEST(string_as_context)
 MSTCH_TEST(two_in_a_row)
 MSTCH_TEST(two_sections)
+MSTCH_TEST(unescaped)
 MSTCH_TEST(whitespace)
 MSTCH_TEST(zero_view)