Bad Error Messages

I’m surprised programmers don’t talk more about error messages. We encounter them every day, yet you rarely see any constructive discussion about them, maybe

Let’s take Python for example:

IndexError and ValueError

index = 10
empty_list = [1,2,3,4,5,6,7,8,9]
for x in range(1000):
     empty_list[index + x]

Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
IndexError: list index out of range

empty_list.index('hehe')

Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
ValueError: list.index(x): x not in list

Printing out which index was out of range would definitely save me a minute or more, not to mention how annoying this is for newbies.

ValueError: 10 not in list [1,2,3,4 ...]

Paranthesis of hell

>>> if 1:
    ...     test = ((1,2, 3)
    ...     test2 = None
File "<stdin>", line 3
    test2 = None
         ^
SyntaxError: invalid syntax

Python forums are full of these questions. Would it be so hard to add (“Maybe you’re missing an end parathesis?”)

In general, I try to suggest solutions and provide some context to the error, that way it’s much easier for other people to debug.