On Wed, Sep 28, 2011 at 9:11 AM, Evan Laforge
For real use, you are right. But to teach list programming to beginners, I think this is necessary. For instance, I would explain how to process String without regular expressions.
I still argue that this is a bad idea. To an extent, functional programmers tend to focus too much on lists as the be-all and end-all of data structures. Whilst lists are great at what they do and generally serve as a good "intermediary" data structure (e.g. converting a Map k a to a Seq (k,a) ), we should not be abusing them to do _everything_.
Also, as an aside, I tend to use lists for everything at first and then convert to a more appropriate data structure later if profiling shows a performance problem. The thing is, several times I've switched to a theoretically more appropriate type (e.g. dlist for repeated appends, Sequence for adds and drops from both ends, AppendList for large appends on both ends) and performance got significantly worse. I don't fully understand why, but my theories are that lists have some nice properties, like 'xs++[]' can immediately reduce to 'xs', and their simplicity counts for a lot (e.g. an AppendList may have multiple pointers per element).