The following is an implementation of tail recursion modulo cons optimization, resulting in a fully tail recursive code. It copies the input structure and then appends the new element to it, by mutation, in the top-down manner. Since this mutation is done to its internal freshly-created data, it is still functional on the outside (does … Read more
Short answer Bypass the default evaluation rules and do not evaluate the expression (symbol or s-exp), passing it along to the function exactly as typed. Long Answer: The Default Evaluation Rule When a regular (I’ll come to that later) function is invoked, all arguments passed to it are evaluated. This means you can write this: … Read more
(symbol-function ‘foo) is a Generalized Variable in elisp, so you can use: (setf (symbol-function ‘forward-word) #’backward-word) as an alternative to: (fset ‘forward-word #’backward-word) (As a side-note, you can do the same thing with cl-letf as a replacement for the deprecated flet when you want to override a function using dynamic scope.)