Python’s easy and simple syntax sometimes mislead developers - especially if they are new to the language. This blog covers some of the top mistakes that even an advanced Python developer can make.
- INCORRECT INDENTATION
Numerous Python characteristics depend on indentation. Like, when you make a new class, everything in that class is indented under the class declaration. The same is true for decision, loop, and other structural statements. If you find that your code is executing a task when it really shouldn’t, start reviewing the indentation you’re using.
- MISPLACING PUNCTUATION
This error happens when developer place punctuation in the wrong place and creates a completely different result. Remember that you must include a colon at the end of each structural statement. In addition, parentheses placement is critical. For example, (1 + 2) * (3 + 4), 1 + ((2 * 3) + 4), and 1 + (2 * (3 + 4)) all give different results.
- APPLYING ASSIGNMENT OPERATOR INSTEAD OF THE EQUALITY OPERATOR
Often Developers use the equality operator (==) instead of assignment operator (=) when they perform a comparison between two objects or value. The assignment operator places an object or value within a variable and doesn’t compare anything.
- USING THE WRONG LOGICAL OPERATOR
Most of the operators don’t present developers with problems, but the logical operators do. Remember to use and to clarify when both operands must be true and or when either of the operands can be true.
- WRONG CAPITALIZATION
Python is case sensitive, so MyVar is different from myvar and MYVAR. Always check capitalization when you find that you can’t access a value you expected to access.
- CREATING COUNT-BY-ONE ERRORS ON LOOPS
You must remember that a loop doesn’t count the last number you specify in a range. So if you specify the range [1:11], you actually get output for values between 1 and 10.
- SPELLING SOMETHING WRONG
Even seasoned developers suffer from spelling errors at times. Making sure that you use a common approach while naming variables,classes, and functions does help. However, even a consistent naming scheme won’t always prevent you from typing MyVer when you meant to type MyVar.
- IGNORANCE OF PYTHON SCOPE RULES
Python uses a distinctive method for scoping variables when compared to other programming languages. For example, it allows accessing the variables declared inside loops or if statements from outside. It could be a bit confusing for someone coming from a C/C++ background.
MISUSING THE __INIT__ METHOD
The __init__ methods are used as constructors in Python. It automatically gets called when Python allocates memory to a new class object. The purpose of this method is to set the values of instance members for the class object. Trying to explicitly return a value from the __init__ method implies that you want to deviate from its actual purpose.
A solution for this is to add a new property and move the desired logic to a different instance method.
NAME CLASHING WITH PYTHON STANDARD LIBRARY MODULES
Python is abundant with its large number of library modules which comes out of the box. But problems can occur if you run into a name clash between the name of one of your modules and a module with the same name in the standard library that ships with Python.
This will result in importing another library which in turn tries to import the Python Standard Library version of a module but, since you have a module with the same name, the other package mistakenly imports your version instead of the one within the Python Standard Library.
Care should, therefore, be taken to avoid using the same names as that of standard Python libraries
Rahul Tripathi has been writing custom content for over 3 years. He provides writing, coaching and editing services. MCA graduated from University of Delhi with bachelor’s degree in English Literature. Currently, Rahul is focusing on writing content about Python Programming