lua-users home
lua-l archive

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

Rici Lake wrote:



On 27-Nov-05, at 12:52 PM, Chris Marrin wrote:
It is pretty easy to store a 'length' property in a table to identify how many numeric keys it has.
Sure. I think Mike was talking about the general iteration case, though, not the numeric one.
I found that technique ALMOST works in Lua. If a table has entries for numeric keys 1,2,12 and 17, and I set the length property to 17 then I can go: 

    for i=1,t.length do
        print(t[i])
    end
and I will get all the numbers printing out, with nils in the slots that don't have a numeric index. 


In fact, that's the way it was at one time (with 'n' in place of 'length').



But I found that attempting to set:

    t[0] = "hello"
does not work. When I read this back, it prints nil. Is this true, or do I have a bug in my logic somewhere? 


You have a bug in your logic somewhere.

Lua 5.1 (beta)  Copyright (C) 1994-2005 Lua.org, PUC-Rio
 > t = {}
 > t[0] = "Hello"
 > =t[0]
Hello

Lua 5.0.2  Copyright (C) 1994-2004 Tecgraf, PUC-Rio
 > t = {}
 > t[0] = "Hello"
 > =t[0]
Hello


Hmmm. Ok, thanks for doing the test!!!

--
chris marrin              ,""$, "As a general rule,don't solve puzzles
chris@marrin.com        b`    $  that open portals to Hell" ,,.
        ,.`           ,b`    ,`                            , 1$'
     ,|`             mP    ,`                              :$$'     ,mm
   ,b"              b"   ,`            ,mm      m$$    ,m         ,`P$$
  m$`             ,b`  .` ,mm        ,'|$P   ,|"1$`  ,b$P       ,`  :$1
 b$`             ,$: :,`` |$$      ,`   $$` ,|` ,$$,,`"$$     .`    :$|
b$|            _m$`,:`    :$1   ,`     ,$Pm|`    `    :$$,..;"'     |$:
P$b,      _;b$$b$1"       |$$ ,`      ,$$"             ``'          $$
 ```"```'"    `"`         `""`        ""`                          ,P`