I am trying to make an inventory program to use in an RPG. The program needs to be able to add and remove things and then add them to a list. This is what I have so far:
inventory=["sword","potion","armour","bow"]
print[inventory]
print["\ncommands: use [remove] and pickup [add]"]
selection=input["choose a command [use/pickup]"]
if selection=="use":
print[inventory]
remove=input["What do you want to use? "]
inventory.remove[remove]
print[inventory]
elif selection=="pickup":
print[inventory]
add=input["What do you want to pickup? "]
newinv=inventory+str[add]
print[newinv]
When I run this and try to pick something up, I get this error:
Traceback [most recent call last]:
File "H:/Year 10/Computing/A453/Python Programs/inventory.py", line 15, in
newinv=inventory+str[add]
TypeError: can only concatenate list [not "str"] to list
Does any one have a fix for this, it would be greatly appreciated.
asked Oct 16, 2013 at 8:54
I think what you want to do is add a new item to your list, so you have change the line newinv=inventory+str[add] with this one:
newinv = inventory.append[add]
What you are doing now is trying to concatenate a list with a string which is an invalid operation in Python.
However I think what you want is to add and delete items from a list, in that case your if/else block should be:
if selection=="use":
print[inventory]
remove=input["What do you want to use? "]
inventory.remove[remove]
print[inventory]
elif selection=="pickup":
print[inventory]
add=input["What do you want to pickup? "]
inventory.append[add]
print[inventory]
You don't need to build a new inventory list every time you add a new item.
answered Oct 16, 2013 at 8:56
jabaldonedojabaldonedo
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0
That's not how to add an item to a string. This:
newinv=inventory+str[add]
Means you're trying to concatenate a list and a string. To add an item to a list, use the
list.append[] method.
inventory.append[add] #adds a new item to inventory
print[inventory] #prints the new inventory
Hope this helps!
answered Oct 16, 2013 at 8:58
aIKidaIKid
24.8k4 gold badges38 silver badges65 bronze badges
3
You can use:
newinv=inventory+[add]
but using append is better since it doesn't create a new list:
inventory.append[add]
answered Oct 30, 2019 at 11:15
alperealpere
1,02617 silver badges24 bronze badges
I have a solution for this. First thing that add is already having a string value as input[] function by default takes the input as string. Second thing that you can use append method to append value of add variable in your list.
Please do check my code I have done some modification : - {1} You can enter command in capital or small or mix {2} If user entered wrong command then your program will ask to input command again
inventory = ["sword","potion","armour","bow"] print[inventory] print["\ncommands : use [remove item] and pickup [add item]"] selection=input["choose a command [use/pickup] : "] while True: if selection.lower[]=="use": print[inventory] remove_item=input["What do you want to use? "] inventory.remove[remove_item] print[inventory] break
elif selection.lower[]=="pickup":
print[inventory]
add_item=input["What do you want to pickup? "]
inventory.append[add_item]
print[inventory]
break
else:
print["Invalid Command. Please check your input"]
selection=input["Once again choose a command [use/pickup] : "]
answered Nov 1, 2020 at 16:29
Let me fix your code
inventory=["sword", "potion", "armour", "bow"]
print[inventory]
print["\ncommands: use [remove] and pickup [add]"]
selection=input["choose a command [use/pickup]"]
if selection == "use":
print[inventory]
inventory.remove[input["What do you want to use? "]]
print[inventory]
elif selection == "pickup":
print[inventory]
add=input["What do you want to pickup? "]
newinv=inventory+[str[add]] #use '[str[add]]' or list[str[add]]
print[newinv]
The error is you are adding string and list, you should use list or [] to make the string become list type
answered Oct 30, 2019 at 11:19