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Python

Posted by Konrad Gołda
Konrad Gołda
735 Points

Console error possible?

Hi,

is there a console error possible, or my computer is just not good enough or something?

#in REPL, instead of ", yum" I have typed:
dessert += ", YUMMY IN MY TUMMY"

#but the result was like this:
>>> dessert                                                                                                                  
'chocolate and marshmallows an                                                                                               
MMY'   

#later on, when I typed command:
>>> dessert

# for the second time, my console displayed this:


>>> dessert = dessert + " and                                                                                                
>>> dessert                                                                                                                  
'chocolate and marshmallows an                                                                                               
>>> dessert += ", YUMMY IN MY                                                                                                
>>> dessert                                                                                                                  
'chocolate and marshmallows an                                                                                               
MMY'                                                                                                                         
>>> dessert                                                                                                                  
'chocolate and marshmallows an                                                                                               
MY'                                                                                                                          
>>>                                                                                                                          
KeyboardInterrupt                                                                                                            
>>>                                                                                                                          
KeyboardInterrupt                                                                                                            
>>>                      


#so it cutted a lot of a string. Can someone explain why this occurred and how to deal with this?
#THANKS! ;)

1 Answer

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,732 Points
Jeff Muday
Jeff Muday
Treehouse Moderator 28,732 Points

Order is important when you run Python (and the REPL). Note that dessert must be defined before you can use the "+=" operator.

If dessert is not defined it will throw an error like shown below.

Python 3.7.4 (tags/v3.7.4:e09359112e, Jul  8 2019, 20:34:20) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license()" for more information.
>>> dessert += ", yum"
Traceback (most recent call last):
  File "<pyshell#0>", line 1, in <module>
    dessert += ", yum"
NameError: name 'dessert' is not defined

If dessert were defined before you use the "+=" operator, like below, it would work.

>>> dessert = 'chocolate and marshmallows'
>>> dessert += ", yum"
>>> print(dessert)
chocolate and marshmallows, yum