Strings != ""

05-21-2009, 10:22 PM

aka strings ALLWAYS should be null and not "". and never do comparisions like this

JASS:

if str!="" then
endif

cause after map is saved and loaded (game save) this comparision will fail. and only null will succeed. i mean

JASS:

if str!=null then
endif

maybe it's obvious. but i bet someone have such checks ;P (including me well i had.)
It may lead to malfunctions or even to game crash (if operationg with gamecache or ExecuteFunc or similar).

and other "news" are what on bnet (now after the update) all maps with code returns will be unable to be hosted.

JASS:

function xxx takes nothing returns code
    return null
endfunction
// as example

will cripple the map. but in most cases no one need code ^_^ but it's just for info.

05-21-2009, 10:31 PM	#2
Silvenon	Well, doesn't everybody do both? JASS: if str!="" and str!=null then endif At least I do. Except for crashes when using gamecache or ExecuteFunc (etc.) there are no problems with that then, right?

05-22-2009, 01:59 AM	#3
MaD[Lion]	why use both when u can use null

05-22-2009, 04:42 AM

grim001

Quote:

Originally Posted by Toadcop

and other "news" are what on bnet (now after the update) all maps with code returns will be unable to be hosted.

If this is true, maybe jasshelper should give a compile warning about it, at least in debug mode.

05-22-2009, 05:49 AM	#5
Ammorth	Does null still work if you pass "" as a string argument? At one point I didn't think it would (and that "" and null are two different values).

05-22-2009, 10:15 AM

Toadcop

Quote:

At least I do. Except for crashes when using gamecache or ExecuteFunc (etc.) there are no problems with that then, right?

Quote:

It may lead to malfunctions

aka depends on your algorithms...

Quote:

Does null still work if you pass "" as a string argument? At one point I didn't think it would (and that "" and null are two different values).

yes they are different. BUT no function (afaik) does return "" until you write one or something =)

Quote:

If this is true, maybe jasshelper should give a compile warning about it, at least in debug mode.

yes maybe. i don't have bnet. so if someone could check it ? (my friend told me what it fail well and i belive him...)

05-22-2009, 02:30 PM

Vexorian

Quote:

Originally Posted by Silvenon

Well, doesn't everybody do both?

JASS:

if str!="" and str!=null then
endif

At least I do. Except for crashes when using gamecache or ExecuteFunc (etc.) there are no problems with that then, right?

I do.

Alternatively (StringLength(s) > 0)

Actually I think this was known ever since the first Jass vault's times. Hence the reason I always compared with both "" and null.

05-22-2009, 02:31 PM

Vexorian

Quote:

and other "news" are what on bnet (now after the update) all maps with code returns will be unable to be hosted.

I wonder if this is related with some odd optimizer bug reports I've been getting.