cl-nsubst
cl-nsubst is an autoloaded compiled Lisp function in `cl-seq.el
'.
(cl-nsubst NEW OLD TREE [KEYWORD VALUE]...)
Substitute NEW for OLD everywhere in TREE (destructively).
Any element of TREE which is `eql' to OLD is changed to NEW (via a call
to `setcar').
Keywords supported: :test :test-not :key