Software development topics I've changed my mind on

This is less of a mind-was-changed case and more just controversial, but... Checked Exceptions were a fundamentally good idea. They just needed some syntactic sugar to help redirect certain developers into less self-destructive ways of procrastinating on proper error handling.

In brief for non-Java folks: Checked Exceptions are a subset of all Exceptions. To throw them, they must be part of the function's type signature. To call that function, the caller code must make some kind of decision about what to do when that Checked Exception arrives. [0] It's basically another return type for the method, married with the conventions and flow-control features of Exceptions.

[0] Ex: Let it bubble up unimpeded, adding it to your own function signature; catch it and wrap it in your own exception with a type more appropriate to the layer of abstraction; catch it and log it; catch it and ignore it... Alas, many caught it and wrapped it in a generic RuntimeException.

This is not, of course, the only way that checked exceptions can be utilized. But, all too often, that is by far the easiest way to reason on them. They represent a decision that needs to be bubbled up to the operator of the overall system.

Worse, the easy way to explain how the system should resume, is to go back to where the exception happened and to restart with some change in place. Disk was full, continue, but write to a new location. That is, having the entire stack unrolled means you wind up wanting the entire process reentrant. But that is an actively hostile way to work for most workflows. Imagine if, on finding a road was closed, a cab driver took you back to pick up location to ask what you want to do about it.

If it is not something that you want to unwind the stack, or bubble up to the users, then you go through effort to wrap it so that it is another value that is being processed.

I'm not saying exceptions are good, but I am saying that they do represent the most common error handling pattern.