Move enum option handling in enum.hh and refactor enum options

src/client.cc

@@ -236,15 +236,15 @@ void Client::check_if_buffer_needs_reloading()
         return;
 
     Buffer& buffer = context().buffer();
-    auto reload = context().options()["autoreload"].get<YesNoAsk>();
-    if (not (buffer.flags() & Buffer::Flags::File) or reload == No)
+    auto reload = context().options()["autoreload"].get<Autoreload>();
+    if (not (buffer.flags() & Buffer::Flags::File) or reload == Autoreload::No)
         return;
 
     const String& filename = buffer.name();
     timespec ts = get_fs_timestamp(filename);
     if (ts == InvalidTime or ts == buffer.fs_timestamp())
         return;
-    if (reload == Ask)
+    if (reload == Autoreload::Ask)
     {
         m_ui->info_show(
             format("reload '{}' ?", buffer.display_name()),

src/client.hh

@@ -7,6 +7,7 @@
 #include "safe_ptr.hh"
 #include "utils.hh"
 #include "option_manager.hh"
+#include "enum.hh"
 
 namespace Kakoune
 {
@@ -84,6 +85,24 @@ private:
     SafePtr<Buffer> m_last_buffer;
 };
 
+enum class Autoreload
+{
+    Yes,
+    No,
+    Ask
+};
+
+constexpr Array<EnumDesc<Autoreload>, 5> enum_desc(Autoreload)
+{
+    return { {
+        { Autoreload::Yes, "yes" },
+        { Autoreload::No, "no" },
+        { Autoreload::Ask, "ask" },
+        { Autoreload::Yes, "true" },
+        { Autoreload::No, "false" }
+    } };
+}
+
 }
 
 #endif // client_hh_INCLUDED

src/enum.hh

@@ -0,0 +1,76 @@
+#ifndef enum_hh_INCLUDED
+#define enum_hh_INCLUDED
+
+#include "flags.hh"
+#include "string.hh"
+#include "exception.hh"
+#include "containers.hh"
+
+namespace Kakoune
+{
+
+template<typename T, size_t N>
+struct Array
+{
+    constexpr size_t size() const { return N; }
+    constexpr const T& operator[](int i) const { return m_data[i]; }
+    constexpr const T* begin() const { return m_data; }
+    constexpr const T* end() const { return m_data+N; }
+
+    T m_data[N];
+};
+
+template<typename T> struct EnumDesc { T value; StringView name; };
+
+template<typename Flags, typename = decltype(enum_desc(Flags{}))>
+EnableIfWithBitOps<Flags, String> option_to_string(Flags flags)
+{
+    constexpr auto desc = enum_desc(Flags{});
+    String res;
+    for (int i = 0; i < desc.size(); ++i)
+    {
+        if (not (flags & desc[i].value))
+            continue;
+        if (not res.empty())
+            res += "|";
+        res += desc[i].name;
+    }
+    return res;
+}
+
+template<typename Enum, typename = decltype(enum_desc(Enum{}))>
+EnableIfWithoutBitOps<Enum, String> option_to_string(Enum e)
+{
+    constexpr auto desc = enum_desc(Enum{});
+    auto it = find_if(desc, [e](const EnumDesc<Enum>& d) { return d.value == e; });
+    kak_assert(it != desc.end());
+    return it->name.str();
+}
+
+template<typename Flags, typename = decltype(enum_desc(Flags{}))>
+EnableIfWithBitOps<Flags> option_from_string(StringView str, Flags& flags)
+{
+    constexpr auto desc = enum_desc(Flags{});
+    flags = Flags{};
+    for (auto s : split(str, '|'))
+    {
+        auto it = find_if(desc, [s](const EnumDesc<Flags>& d) { return d.name == s; });
+        if (it == desc.end())
+            throw runtime_error(format("invalid flag value '{}'", s));
+        flags |= it->value;
+    }
+}
+
+template<typename Enum, typename = decltype(enum_desc(Enum{}))>
+EnableIfWithoutBitOps<Enum> option_from_string(StringView str, Enum& e)
+{
+    constexpr auto desc = enum_desc(Enum{});
+    auto it = find_if(desc, [str](const EnumDesc<Enum>& d) { return d.name == str; });
+        if (it == desc.end())
+            throw runtime_error(format("invalid enum value '{}'", str));
+    e = it->value;
+}
+
+}
+
+#endif // enum_hh_INCLUDED

src/flags.hh

@@ -12,8 +12,11 @@ struct WithBitOps : std::false_type {};
 template<typename Flags>
 using UnderlyingType = typename std::underlying_type<Flags>::type;
 
-template<typename Flags>
-using EnableIfWithBitOps = typename std::enable_if<WithBitOps<Flags>::value>::type;
+template<typename Flags, typename T = void>
+using EnableIfWithBitOps = typename std::enable_if<WithBitOps<Flags>::value, T>::type;
+
+template<typename Flags, typename T = void>
+using EnableIfWithoutBitOps = typename std::enable_if<not WithBitOps<Flags>::value, T>::type;
 
 template<typename Flags, typename = EnableIfWithBitOps<Flags>>
 constexpr Flags operator|(Flags lhs, Flags rhs)

src/input_handler.hh

@@ -103,6 +103,26 @@ private:
     int    m_handle_key_level = 0;
 };
 
+enum class AutoInfo
+{
+    None = 0,
+    Command = 1 << 0,
+    OnKey   = 1 << 1,
+    Normal  = 1 << 2
+};
+
+template<>
+struct WithBitOps<AutoInfo> : std::true_type {};
+
+constexpr Array<EnumDesc<AutoInfo>, 3> enum_desc(AutoInfo)
+{
+    return { {
+        { AutoInfo::Command, "command"},
+        { AutoInfo::OnKey, "onkey"},
+        { AutoInfo::Normal, "normal" }
+    } };
+}
+
 bool show_auto_info_ifn(StringView title, StringView info, AutoInfo mask, const Context& context);
 
 template<typename Cmd>

src/main.cc

@@ -224,7 +224,7 @@ void register_options()
                        }), OptionFlags::None);
     reg.declare_option("autoreload",
                        "autoreload buffer when a filesystem modification is detected",
-                       Ask);
+                       Autoreload::Ask);
     reg.declare_option("ui_options",
                        "colon separated list of <key>=<value> options that are "
                        "passed to and interpreted by the user interface\n"

src/option_types.hh

@@ -8,6 +8,7 @@
 #include "array_view.hh"
 #include "id_map.hh"
 #include "flags.hh"
+#include "enum.hh"
 
 #include <tuple>
 #include <vector>
@@ -192,101 +193,6 @@ inline String option_to_string(const LineAndColumn<EffectiveType, LineType, Colu
     return format("{},{}", opt.line, opt.column);
 }
 
-enum YesNoAsk
-{
-    Yes,
-    No,
-    Ask
-};
-
-inline String option_to_string(YesNoAsk opt)
-{
-    switch (opt)
-    {
-        case Yes: return "yes";
-        case No:  return "no";
-        case Ask: return "ask";
-    }
-    kak_assert(false);
-    return "ask";
-}
-
-inline void option_from_string(StringView str, YesNoAsk& opt)
-{
-    if (str == "yes" or str == "true")
-        opt = Yes;
-    else if (str == "no" or str == "false")
-        opt = No;
-    else if (str == "ask")
-        opt = Ask;
-    else
-        throw runtime_error(format("invalid value '{}', expected yes, no or ask", str));
-}
-
-template<typename T> struct EnumInfo;
-
-template<typename Flags,
-         typename = EnableIfWithBitOps<Flags>,
-         typename = decltype(EnumInfo<Flags>::values(), EnumInfo<Flags>::names())>
-String option_to_string(Flags flags)
-{
-    auto names = EnumInfo<Flags>::names();
-    auto values = EnumInfo<Flags>::values();
-    String res;
-    for (int i = 0; i < values.size(); ++i)
-    {
-        if (not (flags & values[i]))
-            continue;
-        if (not res.empty())
-            res += "|";
-        res += names[i];
-    }
-    return res;
-}
-
-template<typename Flags,
-         typename = EnableIfWithBitOps<Flags>,
-         typename = decltype(EnumInfo<Flags>::values(), EnumInfo<Flags>::names())>
-void option_from_string(StringView str, Flags& flags)
-{
-    auto names = EnumInfo<Flags>::names();
-    auto values = EnumInfo<Flags>::values();
-    flags = Flags{};
-    for (auto s : split(str, '|'))
-    {
-        auto it = std::find(names.begin(), names.end(), s);
-        if (it == names.end())
-            throw runtime_error(format("invalid flag value '{}'", s));
-        flags |= values[it - names.begin()];
-    }
-}
-
-enum class AutoInfo
-{
-    None = 0,
-    Command = 1 << 0,
-    OnKey   = 1 << 1,
-    Normal  = 1 << 2
-};
-
-template<>
-struct WithBitOps<AutoInfo> : std::true_type {};
-
-template<> struct EnumInfo<AutoInfo>
-{
-    static ArrayView<const AutoInfo> values()
-    {
-        static constexpr AutoInfo values[] = { AutoInfo::Command, AutoInfo::OnKey, AutoInfo::Normal };
-        return { values };
-    }
-
-    static ArrayView<const StringView> names()
-    {
-        static constexpr StringView names[] = { "command", "onkey", "normal" };
-        return { names };
-    }
-};
-
 enum class DebugFlags
 {
     None  = 0,
@@ -297,20 +203,13 @@ enum class DebugFlags
 template<>
 struct WithBitOps<DebugFlags> : std::true_type {};
 
-template<> struct EnumInfo<DebugFlags>
+constexpr Array<EnumDesc<DebugFlags>, 2> enum_desc(DebugFlags)
 {
-    static ArrayView<const DebugFlags> values()
-    {
-        static constexpr DebugFlags values[] = { DebugFlags::Hooks, DebugFlags::Shell };
-        return { values };
-    }
-
-    static ArrayView<const StringView> names()
-    {
-        static constexpr StringView names[] = { "hooks", "shell" };
-        return { names };
-    }
-};
+    return { {
+        { DebugFlags::Hooks, "hooks" },
+        { DebugFlags::Shell, "shell" }
+    } };
+}
 
 }