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>From: Edgar Toernig <>

>1. Allow the $if/$ifnot statement to test if debugging is turned on
>   so that one can add additional debugging code in lua programs.

The purpose of $debug is to enable better error messages, not to support
user-level debugging.
I think you could do what you want using a global variable, say DEBUG,
and then write:

    print("x.n=", getn(x))
    foreach(x, function(i,v) assert(type(i)=="number", "bad x") end)

To enable this code using the standard standalone interpreter, you can simply
do	lua DEBUG=1 myfile.lua

>2. The second argument to the next() function should be optional so that
>   next(foo, nil) is the same as next(foo).  I use next() regularly to test
>   if a table is empty (if next(tab) then print"not empty" end) and the 
>   additional nil is disturbing and inconsistent.

Using "next" to test whether a table is empty is a clever idea, but it got me
thinking *why* you would want to do this.

Anyway, the request sounds reasonable to me. We'll see...