Add usage samples

[flexferrum]

Add usage samples for:

• Web (based on boost.beast)
• Code generation (based on cppast)

[flexferrum]

@Manu343726 , would you like to add your cppast/tinyrefl template examples here?

[Manu343726]

Whenever I make it work, sure ;)

[flexferrum]

Thanks!

[Manu343726]

BTW something like this should work right now:

#include <cppast/libclang_parser.hpp>
#include <tinyrefl/tool/model/cppast/jinja2reflection.hpp>
#include <jinja2cpp/template.h>

using namespace tinyrefl::tool::model;

int main()
{
    using parser_t = cppast::simple_file_parser<cppast::libclang_parser>;
    cppast::cpp_entity_index index;
    parser_t                 parser{type_safe::ref(index)};
    parser_t::config         config;
    config.set_flags(cppast::cpp_standard::cpp_11);

    auto file = parser.parse("my_enum.hpp", config);
    jinja2::ValuesMap variables{
        {"file", jinja2::Reflect(make_entity_ref(index, file.value()))}};

        jinja2::Template tmpl;
    tmpl.Load(R"(
{% for enum in file.enums %}
{{enum.fullname}} from_string(const std::string& str)
{
{% for value in enum.values %}
    if((str == "{{value.name}}") ||
       (str == "{{value.qualifiedname}}") ||
       (str == "{{value.fullname}}"))
    {
        return {{value.fullname}};
    }
{% endfor %}

    throw std::logic_error{"Invalid {{enum.fullname}} value name"};
}
{% endfor %}
)");
    std::ofstream output{"my_enum_from_string.cpp"};
    tmpl.Render(output, variables);
}

[flexferrum]

Contemporary classics. :D