can an item in inventory have no prefab ?

[whismerhill]

hi,

so my code has a loop that goes through all inventory items. I verified that item is not nil already however I got a rare crash where this code :

if (item["Light"] or recipes[item.prefab].tab == RECIPETABS.LIGHT then

returned an error because can't index nil. so I'm wondering if I should check that item.prefab is not nil globally or locally

e.g. can a valid item have no prefab ???

I'm wondering cause so far I can't reproduce the crash.

Thanks.

[Mobbstar]

maybe the item itself is nil?

Anyways, some dummy prefabs spawn before anything else and don't have a prefab name.

[whismerhill]

well I don't think it's possible since there's a : "if item then" before that

and ok that means I should be safe to verify that all items in inventory have a prefab globally before it process any of them.

if item and item.prefab then

thanks.

Edited June 17, 2016 by whismerhill

[DarkXero]

On some very particular circumstances, the prefab of an item can be nil, I guess.

But that's not the issue here at all.

Not all items have recipes.

recipes[item.prefab] is nil if the item can't be crafted.

[whismerhill]

well I agree with you darkxero

however why would that be a problem at all ?

you mean it can't do the operation : " nil == somevalue " and so  return false ?

so before doing that I should add something like

if (item["Light"] or function(item,recipes) if recipes[item.prefab] then return (recipes[item.prefab].tab == RECIPETABS.LIGHT) else return false end end) then

ho while writing it I realize that maybe what it doesn't like is the ".tab" over a nil value ?

sorry I'm a bit of a newb

Edited June 18, 2016 by whismerhill

[Mobbstar]

2 hours ago, whismerhill said:

however why would that be a problem at all ?

Just do something like you do for whether the item exists at all:

if (item["Light"] or (recipes[item.prefab] and recipes[item.prefab].tab == RECIPETABS.LIGHT) then