Test some variable shadowing

scm/inc/tests.scm

@@ -110,4 +110,6 @@
(do-tests "3.5 - local variables"
  '[["(let ((x 3) (y 4)) (+ x y))" "7\n"]
    ["(let ((b #t)) (boolean? b))" "#t\n"]])
    ["(let ((b #t)) (boolean? b))" "#t\n"]
    ["(let ((x 3) (x 4)) x)" "4\n"]
    ["(let ((x 3)) (let ((x 4)) x))" "4\n"]])