Metatable shennigans for optional map arguments

runtime/lua/testplugin.lua

@@ -16,7 +16,8 @@ end
 
 local function init()
   plugin:map("<F2>", stuff)
-  plugin:map("<buffer> <", stuff2)
+  plugin.map = plugin.map.buffer.silent
+  plugin:map("<", stuff2)
 end
 
 return {

runtime/lua/tycho/init.lua

@@ -5,13 +5,16 @@ local command = nvim.nvim_command
 
 local messages = {}
 local functions = {}
+local map_args = " "
 
 local function map_to_ns(keys, ns)
+  map_args = (map_args == " " and map_args) or map_args.." "
   local keys_rhs = keys:gsub("<", "<lt>")
   local rhs = "lua require('tycho').functions["..
                   tostring(ns).."]['"..keys_rhs.."']()"
   table.insert(messages, { rhs = rhs })
-  command("map "..keys.." <Cmd>"..rhs.."<CR>")
+  command("map"..map_args..keys.." <Cmd>"..rhs.."<CR>")
+  map_args = " "
 end
 
 local function debug()
@@ -21,8 +24,9 @@ local function debug()
   command("put =tycho_fns")
 end
 
+local map = {}
 
-local function map(self, keys, fn)
+local function fn_map(self, keys, fn)
   assert(type(keys) == "string", "Must pass a string as 2nd argument to map")
   assert(type(fn) == "function", "Must pass a function as 2nd argument to  map")
 
@@ -40,6 +44,18 @@ local function map(self, keys, fn)
   map_to_ns(keys, ns)
 end
 
+local function map_index(k)
+  if k == "buffer" then
+    map_args = map_args.."<buffer>"
+  elseif k == "silent" then
+    map_args = map_args.."<silent>"
+  end
+  return map
+end
+
+setmetatable(map, { __call = function(self, plugin, keys, fn) return fn_map(plugin, keys, fn) end,
+                    __index = function(self, k) return map_index(k) end })
+
 local function new_plugin(name)
   -- TODO(KillTheMule): This code assumes that subsequent calls with the same
   --                    name return the same ns. Make sure of that, or adapt