def test_walk2(): v, w, x, y = variables("v, w, x, y") substitution = Substitution({x: y, v: x, w: x}) assert substitution.walk(x) is y assert substitution.walk(v) is y assert substitution.walk(w) is y
def test_walk1(): a, w, x, y, z = variables("a, w, x, y, z") substitution = Substitution({z: a, x: w, y: z}) assert substitution.walk(x) is w assert substitution.walk(y) is a assert substitution.walk(z) is a
def test_extend_and_walk(): x, y, z = variables("x, y, z") s = Substitution({z: x, y: z}) s = s.extend(x, 'e') assert s.walk(y) == 'e'
def test_walk3(): b, v, w, x, y, z = variables("b, v, w, x, y, z") substitution = Substitution({x: b, z: y, w: (x, "e", z)}) assert substitution.walk(w) == (x, "e", z)