lua-users home
lua-l archive

[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index] [Thread Index]

On 4 February 2011 06:59, Wesley Smith <> wrote:
>> Yep.  "oldprint(), which is a reference to *the original* print()"
>> If none of these functions were called "print" or anything like it, and there weren't languages where print was part of the language and not just a function, I think it'd all be much simpler to understand.
> Functions aren't really references but values.  If you assign print to
> oldprint, you can't modify oldprint by somehow modifying print.
> Functions are more like numbers.  They're first class values.

As I see it a reference can be a first class value, for example tables
are first class values and are references. If a type is immutable like
Lua strings or numbers there is not effective difference, in fact
strings are managed as hashes of a single string copy.
For functions you can do

  local v = 1
  a = function () print(v) end
b = a
debug.setupvalue(b, 1, 2)

To me this means that b is a reference to the same function as a. Am I correct?