[agumonkey]

yeah it's a strange aspect of that lisp era, it was born in mccarthy's recursive functions over recursive lists.. and then interactive development over global state added as a layer.

i would argue that lispers use of mutability was much more surgical and principled but maybe i'm biased

[dismalaf]

McCarthy's pure Lisp existed only on paper. The first Lisp that ran on a computer had mutable variables, as did Lisp 1.5, Maclisp, etc...

Immutability requires lots of copying and early computers didn't have much memory to spare...