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Leo Razoumov wrote:
On 11/20/08, Matthew Paul Del Buono <> wrote:
Hi list,


 I see that it should be executing the line "return (h(op1, op2))" but that's not what I seem to get in response. I would expect "true" to be the result if the manual stated "return not not (h(op1, op2))" but it doesn't.

 Is this a manual problem, a Lua problem, or am I missing something?

Apparently, the manual and the actual Lua implementation do differ.

In the function "luaV_equalval" defined in  "lvm.c" the last two line are

  callTMres(L, L->top, tm, t1, t2);  /* call TM */
  return !l_isfalse(L->top);

that essentially mean "return not not (h(op1, op2))" as you correctly guessed.
It is different from the pseudo-code in the manual. I would suggest to
correct the manual.

luaV_equalval needs to return a boolean 0 or 1 for comparison with the boolean value in field A in the OP_EQ opcode implementation. This is a straight int comparison, so a 0 or 1 value is mandatory. So in the manual, the pseudo-code's return type of boolean is implicit.

Kein-Hong Man (esq.)
Kuala Lumpur, Malaysia