[Haskell-beginners] "pure" versus "impure" code

[Costello, Roger L.]

Hi Folks,

Is there a web site that defines "pure" versus "impure" code?

My understanding is that:

- Pure code is code that does no I/O

- Impure code is code that does I/O

Is that correct?

Also, it is my understanding that good software design is to isolate/separate the impure code from the pure code. Is that correct? Does that principle apply to all programming languages, or just Haskell?

/Roger