Silly quick question(s).

ID:160174
 
Oct 31 2008, 8:12 pm
I've been using a silly method of checking if a list contains anything because if(the_list) doesn't work. Is there an easy way to make sure lists contain something with a single if statement?


Silly question number two:

When using Boolean operators, see the following:

var/omgimtrue=0
if(!omgimtrue) world<<"uh wat? kthxbai." //returns message.

var/omgimtrue=1
if(!omgimtrue) world<<"o" //returns nada.

And now for the big question:

var/omgimtrue=-1
if(!omgimtrue) world<<"lol" //so I guess -1 is a true value?



I just wanted to clarify, thanks.
Oct 31 2008, 8:45 pm
Speedro wrote:
I've been using a silly method of checking if a list contains anything because if(the_list) doesn't work. Is there an easy way to make sure lists contain something with a single if statement?

if(my_list && my_list.len)


That checks if the list exists and if it has a length.

Silly question number two:

When using Boolean operators, see the following:

var/omgimtrue=0
> if(!omgimtrue) world<<"uh wat? kthxbai." //returns message.
> 
> var/omgimtrue=1
> if(!omgimtrue) world<<"o" //returns nada.
> 
> And now for the big question:
> 
> var/omgimtrue=-1
> if(!omgimtrue) world<<"lol" //so I guess -1 is a true value?

I just wanted to clarify, thanks.

-1 is a value. The ! operator will check for the absence of value. In such case, that's null, 0 and "".
Oct 31 2008, 8:45 pm
 
//This can check if a list has elements. First it checks
//that the value passed is a list, then it checks if the
//list has a length, meaning there's something in it.
#define has_elements(l) (istype(l, /list) && length(l))

var/list
    a = list("bloop", "blarg")
    b = list()

if(has_elements(a))
    world << "Good. :)"
if(has_elements(b))
    world << "Bad. :("


As for question number two, false values are only 0, null, and an empty string. Anything else is true.
Nov 1 2008, 4:40 am
In response to Popisfizzy
Just note that some of those elements can be anything ranging from null to numbers to text.