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Python Python Basics (2015) Shopping List App Break

Posted by Andrew Li
Andrew Li
614 Points

Break function in an assignment

I received an assignment from Phase 4 of Python basics tasks 2/2 after the first video. It asks me to break out of a loop once the current item is STOP. I tried but I am not getting the right results. Please Help!

breaks.py 
def loopy(items):
    print(items) 

    for items == "STOP":
        break
Yamil Pérez
Yamil Pérez
Courses Plus Student 2,054 Points

your code should look like this. def loopy(items): for item in items: if item == "STOP": break print(item) Well just make sure that everything blocks their indentation are right.

Andrew Li
Andrew Li
614 Points

Sorry, it doesn't work. @ Yamil Perez

1 Answer

Jeffrey James
Jeffrey James
2,636 Points
Jeffrey James
Jeffrey James
2,636 Points

So keep in mind what you're iterating over. You have a bunch of items in the list. You iterate over them in order. Within the loop, you need to identify your break condition, which will be if the item is 'stop', or whatever. If that condition hits, then call break, else print out or do whatever to the item.

Here's an example:

In [1]: items = ['go', 'goo', 'goooo', 'stop', 'restart']

In [2]: for x in items:
   ...:     if x is 'stop':
   ...:         break
   ...:     print(x)
   ...:     
go
goo
goooo

A more sophisticated way of perhaps filtering your items without a loop: (still using our items list)

In [3]: [x for x in items if x is not 'stop']
Out[3]: ['go', 'goo', 'goooo', 'restart']

Even more obscure, but a pattern you may see in the wild: (still using our items list)

In [5]: list(filter(lambda x: x is not 'stop', items))
Out[5]: ['go', 'goo', 'goooo', 'restart']

Notice how in the break case above, you never reach an item after the break condition was reached, but when you're filtering using a list comprehension [3] or a filter expression [5], you safely pass over the unwanted item.