Fix teaching.lua even more

nvim/lua/teaching.lua

@@ -12,14 +12,23 @@ local function should_load(path)
         [4] = "third-party",
         [5] = "sfml",
     }
+    local match = {
+        [1] = ".hpp",
+        [2] = ".h",
+        [3] = ".cpp",
+        [4] = ".c",
+    }
     for _, pattern in ipairs(ignore) do
         if string.find(path, pattern, 0, true) then
             return false
         end
     end
-    if ends_with(path, ".h") or ends_with(path, ".cpp") or ends_with(path, ".cpp") or ends_with(path, ".cpp") then
-        return true
+    for _, pattern in ipairs(match) do
+        if ends_with(path, pattern) then
+            return true
+        end
     end
+    return false
 end
 
 function teaching.load()