Add let1, a single argument version of let

[EuAndreh]

(defmacro let1 (var val &body body)
  "A single argument version of LET.
   Usage:

   (let1 a 3
     body)
   ... expands to:

   (let ((a 3))
     body)"
  `(let ((,var ,val))
     ,@body))

Provides: let1 Requires: nothing Author: I wrote this one, but too many people implemented it. License: PD

[stylewarning]

Added. Thanks!