update documentation re no-param-reassign

Great tool. I hope this idea might help.

no-param-reassign is a solid rule for good reason (it’s not intuitive that a function’s arguments is recorded as an array, not a key-value).

However, may I suggest the one time the user can safely ignore this rule: creating an object from an array using reduce. I use the eslint-rules for three reasons (loosely speaking):

1. safety that includes consistent, clean design
2. idiomatic to plug-into norms and thus increase speed of understanding
3. performance without sacrificing on safety

My recommendation would be to describe how avoiding a destructuring call on every iteration of the reducing function likely provides a net benefit when building an object from an array using reduce.

This is such an often used function (reduce), that I believe it merits this special “calling out”.

What do you all think?

- E

[platinumazure]

It’s also worthwhile to note that this is a pretty good use case for inline disable comments. You could use those comments in the cases where acc is a real accumulator in a reduce function, but not allow mutations of acc parameters in other contexts.

That said, I wouldn’t oppose improving the docs with a reduce example.

[eslint-deprecated[bot]]

Unfortunately, it looks like there wasn’t enough interest from the team or community to implement this change. While we wish we’d be able to accommodate everyone’s requests, we do need to prioritize. We’ve found that issues failing to reach accepted status after 21 days tend to never be accepted, and as such, we close those issues. This doesn’t mean the idea isn’t interesting or useful, just that it’s not something the team can commit to.

Thanks for contributing to ESLint and we appreciate your understanding.