if-let
if-let is a Lisp macro in `subr-x.el
'.
(if-let BINDINGS THEN &rest ELSE)
Process BINDINGS and if all values are non-nil eval THEN, else ELSE.
Argument BINDINGS is a list of tuples whose car is a symbol to be
bound and (optionally) used in THEN, and its cadr is a sexp to be
evalled to set symbol's value. In the special case you only want
to bind a single value, BINDINGS can just be a plain tuple.