Depleting Container System

[Bluemith]

So, here is my situation. 

Im trying for a detailed fishing system in my game.  In order to catch fish, you first have to hunt up the bait and of course you dont want so have wriggley worms crawling out of your pockets so you want something to put them in.

once a worm is caught, it is turned into a jar of worms and the amount of "Jar of Worms" you have is how many worms you have : p 

However, that leaves me with the problem of consuming the jar once the last worm is used.  How do i make it so that after the last worm is used the "Jar of Worms" is changed back into "An Empty Jar" instead of being consumed?

thanks a ton!

 

[Muffins .org]

How about each time catching a worm add a variable. each time using one reduce a variable.
the amount of 'Jar of Worms'=the amount of the variable
if the variable=0, then the player gets an empty jar.

 

[Bluemith]

Thank you!