[Guvante]

I am confused as to what this has to do with the author's point. He isn't saying purity is hard to use, he is saying the features of Rust make a truly pure function hard to define.

The author seemed to imply that pure if easily used would be a great feature, he just doesn't think that the language that Rust defines is a good match due to the ease of tainting a function.

[christianpbrink]

I agree that that's his point. I just wanted to put in a plug for Haskell being appropriate for many, many application development use cases, because there's a misconception that it's only useful in mathy or academic scenarios.

Again, this guy didn't argue as much; he basically just said it's reasonable for someone developing systems code, code with I/O on every line or something, to conclude she isn't going to be able to reap the benefits of writing pure code in Haskell.

But I think a lot of folks read anything of the form "Haskell isn't appropriate for use case X" as "Haskell's generally impractical". So I wanted to share a different perspective.

[Guvante]

All the Haskell hate I have heard isn't on the language but on developers, not trusting everybody to properly implement the paradigm shift and all that.