Apparently, a common programming interview question these days is to write a function that reverses a linked list. Sometimes they explicitly request a recursive or iterative solution. Like most bare data structure programming, getting this right is surprisingly finicky (which is why most of us these days use nice libraries that provide higher-level abstractions for this).

Just to make sure I'm keeping my tools sharp, I went ahead and implemented this in all four permutations of:

• Recursive or iterative
• In-place or creating a new list

Unsurprisingly to any functional programmer, the recursive immutable list one is the most terse.