sameAs(a, a): true
sameAs(a, b): false
sameAs(a, c): true
sameAs(a, x): true
sameAs(a, y): false
sameAs(a, z): false

sameAs(b, a): left object is null
sameAs(b, b): left object is null
sameAs(b, c): left object is null
sameAs(b, x): left object is null
sameAs(b, y): left object is null
sameAs(b, z): left object is null

sameAs(c, a): true
sameAs(c, b): false
sameAs(c, c): true
sameAs(c, x): true
sameAs(c, y): false
sameAs(c, z): false

sameAs(x, a): true
sameAs(x, b): false
sameAs(x, c): true
sameAs(x, x): true
sameAs(x, y): false
sameAs(x, z): false

sameAs(y, a): false
sameAs(y, b): false
sameAs(y, c): false
sameAs(y, x): false
sameAs(y, y): true
sameAs(y, z): false

sameAs(z, a): left object is null
sameAs(z, b): left object is null
sameAs(z, c): left object is null
sameAs(z, x): left object is null
sameAs(z, y): left object is null
sameAs(z, z): left object is null