Theorem: Pos.le_of_add_le_add_left (Extra/Pos/Lemmas.lean)

State before:
x y z : Pos
⊢ z + x ≤ z + y → x ≤ y
Tactic:
by_toNat
State after:
x y z : Pos
⊢ z.toNat + y.toNat ≥ z.toNat + x.toNat → y.toNat ≥ x.toNat

State before:
x y z : Pos
⊢ z.toNat + y.toNat ≥ z.toNat + x.toNat → y.toNat ≥ x.toNat
Tactic:
exact Nat.le_of_add_le_add_left
State after:
no goals