Understanding error messages in Python

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Programming[1]


Understanding error messages in Python[edit]

Syntax Errors[edit]

Syntax errors, also known as parsing errors, are perhaps the most common kind of complaint you get while you are still learning Python[2]


Exceptions[edit]

Even if a statement or expression is syntactically correct, it may cause an error when an attempt is made to execute it. Errors detected during execution are called exceptions and are not unconditionally fatal.[3]

How to read an error message[edit]

An error MIGHT look something like this:

1.  File "/Users/bmackenty/Documents/python_scratch_folder/hello_world.py", line 1
2.    print" Hello there" 
3.                      ^
4. SyntaxError: invalid syntax
  • On line 1, we see the name of the file we are running, and the line number for the error.
  • On line 2, we see the actual line of code.
  • On line 3, we see the carat character ^ which is pointing the problem on line 2
  • On line 4, we see the actual error. There are many different types of errors.

One important point. Often, an error happens on the line before the stated error. Please use syntax highlighting and your IDE to help you avoid syntax errors.

References[edit]

anomalous or exceptional conditions requiring special processing – often changing the normal flow of program execution

anomalous or exceptional conditions requiring special processing – often changing the normal flow of program execution

A unit of abstract mathematical system subject to the laws of arithmetic.