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----- Original Message -----
From: Luiz Henrique de Figueiredo
Date: 7/6/2013 12:26 PM
The only thing I found that appears to be missing is the ability to
determine the actual type of the number.
One shouldn't need to do this but you can do it as follows:

function isinteger(x)
	return tonumber(tostring(x),10)~=nil
This isinteger() function is pretty heavyweight and becomes a garbage collection nightmare when operating over a lot of data. But I guess it can be done inefficiently.

In any case, I wouldn't go so far as to say one shouldn't need to know the type of the number. There are a number of reasons for this. Most of my ideas deal in serialization; another example is below. However, I can also think of cases where I want to ensure the incoming arguments to a function are integers. Related to serialization is proper reflection.

Perhaps there could be a subtype() function or even an extension of type() that either returns two values 'number' and 'integer' or that takes an extra argument to return the actual numeric type?

-- Write nifty binary format
input =
    these_are_floats = { 1.0, 2.0, 3.0, 4.0, 5.0 },
    these_are_integers = { 1, 2, 3, 4, 5 },
    these_are_strings = { "one", "two", "three", "four", "five" },

function WriteBinaryBlob(data)
    if type(data[1]) == 'number' then
        if subtype(data[1]) == 'integer' then
            return struct.pack(string.rep('I', #data), unpack(data))
            return struct.pack(string.rep('f', #data), unpack(data))
    elseif type(data[1]) == 'string' then
        return struct.pack(string.rep('s', #data), unpack(data))

for key, value in pairs(input) do

It would be nice if there was a method to do so in Lua itself.  One use
case is for serializing integer values to disk in text form properly.
tostring does this already.
True, but I may choose not to use tostring().

Anyway, thanks for all of your efforts getting this going!