Points to ponder - Python - spaces vs tabs - unexpected issue

Python, as everyone knows, uses indentation for blocks of code. In my early programming days, when developing code using languages like C, C++, Java and other environments, I used tabs. But over a period of time, I started preferring using spaces for indentation instead of tabs. This was because I found pressing multiple spaces for indentation to be a painful task. Later, after I started using vi (and appreciating it. I used to dislike / hate vi as well, but that is another story), I found that it was possible to configure vi to replace tabs by spaces. so the headache of typing multiple spaces was taken away by using appropriate settings. One additional issue with tabs is that different people used different tab settings. The value of a tab varied from two spaces to four spaces or eight spaces.

Back to our current situation.

These days, I am developing code using Databricks. When developing code in code in Python, I use Notepad++, with the setting turned on to display a space character using an Orange dot and a tab character using an Orange arrow. Such a feature is not available in Databricks (if it is available, I am not aware of it).

Recently this created a problem. I had code that performed an activity on a table, followed by a logging step. As it happens, I decided to replace the logging step by a function call, instead of a notebook run command. When I made the change and executed it, the code crashed. Upon investigation, I found that the issue was because tab characters were present on the line with the logger statement. The unexpected side effect was that the table activity went through, after which Python threw an error due to indentation. This error meant that the table reversal activity was not performed as control never reached that section. I had to add code for a one time execution to reverse the table activity and then continue with standard execution.

Moral of the story 1 -- proper exception handling and graceful exit is very important

Moral of the story 2 -- there has to be a setting in Databricks editor to show tabs and spaces (similar to what Notepad++ has).

#databricks #python #tabs #spaces #points_to_ponder