end
<
The "eq" event is defined as follows:
>lua
       function eq_event (op1, op2)
         if type(op1) ~= type(op2) then  -- different types?
           return false   -- different objects
         end
         if op1 == op2 then   -- primitive equal?
           return true   -- objects are equal
         end
         -- try metamethod
         local h = getcomphandler(op1, op2, "__eq")
         if h then
           return h(op1, op2)
         else
           return false
         end
       end
<
`a ~= b` is equivalent to `not (a == b)`.

"lt":                                                                   *__lt()*
-----
the `<` operation.
>lua
       function lt_event (op1, op2)
         if type(op1) == "number" and type(op2) == "number" then
           return op1 < op2   -- numeric comparison
         elseif type(op1) == "string" and type(op2) == "string" then
           return op1 < op2   -- lexicographic comparison
         else
           local h = getcomphandler(op1, op2, "__lt")
           if h then
             return h(op1, op2)
           else
             error(...);
           end
         end
       end
<
`a > b` is equivalent to `b < a`.

"le":                                                                   *__le()*
-----
the `<=` operation.
>lua
       function le_event (op1, op2)
         if type(op1) == "number" and type(op2) == "number" then
           return op1 <= op2   -- numeric comparison
         elseif type(op1) == "string" and type(op2) == "string" then
           return op1 <= op2   -- lexicographic comparison
         else
           local h = getcomphandler(op1, op2, "__le")
           if h then
             return h(op1, op2)
           else
             h = getcomphandler(op1, op2, "__lt")
             if h then
               return not h(op2, op1)
             else
               error(...);
             end
           end
         end
       end
<
`a >= b` is equivalent to `b <= a`. Note that, in the absence of a "le"
metamethod, Lua tries the "lt", assuming that `a <= b` is equivalent
to `not (b < a)`.

"index":                                                             *__index()*
--------
The indexing access `table[key]`.
>lua
       function gettable_event (table, key)
         local h
         if type(table) == "table" then
           local v = rawget(table, key)
           if v ~= nil then return v end
           h = metatable(table).__index
           if h == nil then return nil end
         else
           h = metatable(table).__index
           if h == nil then
             error(...);
           end
         end
         if type(h) == "function" then
           return h(table, key)      -- call the handler
         else return h[key]          -- or repeat operation on it
       end
<
"newindex":                                                       *__newindex()*
-----------
The indexing assignment `table[key] = value`.
>lua
       function settable_event (table, key, value)
         local h
         if type(table) == "table" then
           local v = rawget(table, key)
           if v ~= nil then rawset(table, key, value); return end
           h = metatable(table).__newindex
           if h == nil then rawset(table, key, value); return end
         else
           h = metatable(table).__newindex
           if h == nil then
             error(...);
           end
         end
         if type(h) == "function" then
           return h(table, key,value)    -- call the handler
         else h[key] = value             -- or repeat operation on it
       end
<
"call":                                                               *__call()*
-------
called when Lua calls a value.
>lua
       function function_event (func, ...)
         if type(func) == "function" then
           return func(...)   -- primitive call
         else
           local h = metatable(func).__call
           if h then
             return h(func, ...)
           else
             error(...)