Re: PRNG for Lua 4.0?

[Dirk Laurie <dirk.laurie@...>]

2013/9/10 Michael Horvath <mikh2161@gmail.com>:

> OK since this code is not working for me, does anyone have a
> suggestion for a different PRNG implementation I could use instead?

We're talking about code that runs under standard Lua 4.0.1
but not on some non-standard Lua 4.0 that has been modified in some
undocumented way by some unidentified game developer.

I.e. the problem is not the code, it's the Lua modification. For example,
Lua 4.0 uses a file called 'config' which contains these lines:

# Lua uses double for numbers. To change this, uncomment one of the lines below.
#NUMBER= -DLUA_NUM_TYPE=double
#NUMBER= -DLUA_NUM_TYPE=float
#NUMBER= -DLUA_NUM_TYPE=long
# Optionally, you may also want change how numbers are converted to strings,
# and vice-versa. Look for LUA_NUMBER in llimits.h and in the rest of the code.

If the developer made Lua use float instead of double, of course any code
that relies on properties like the product of two 16-bit integers being exactly
representable is not going to work.

Run this code under your Lua and tell us the output:

x=1; for k=1,64 do x=2*x; if x-(x-1)~=1 then n=k-1 break end end; print(n)