src/HOL/Nat.thy
changeset 65583 8d53b3bebab4
parent 64876 65a247444100
child 65963 ca1e636fa716
equal deleted inserted replaced
65580:66351f79c295 65583:8d53b3bebab4
  1698   by (fact of_nat_eq_iff [of 0 n, unfolded of_nat_0])
  1698   by (fact of_nat_eq_iff [of 0 n, unfolded of_nat_0])
  1699 
  1699 
  1700 lemma of_nat_eq_0_iff [simp]: "of_nat m = 0 \<longleftrightarrow> m = 0"
  1700 lemma of_nat_eq_0_iff [simp]: "of_nat m = 0 \<longleftrightarrow> m = 0"
  1701   by (fact of_nat_eq_iff [of m 0, unfolded of_nat_0])
  1701   by (fact of_nat_eq_iff [of m 0, unfolded of_nat_0])
  1702 
  1702 
       
  1703 lemma of_nat_1_eq_iff [simp]: "1 = of_nat n \<longleftrightarrow> n=1"
       
  1704   using of_nat_eq_iff by fastforce
       
  1705 
       
  1706 lemma of_nat_eq_1_iff [simp]: "of_nat n = 1 \<longleftrightarrow> n=1"
       
  1707   using of_nat_eq_iff by fastforce
       
  1708 
  1703 lemma of_nat_neq_0 [simp]: "of_nat (Suc n) \<noteq> 0"
  1709 lemma of_nat_neq_0 [simp]: "of_nat (Suc n) \<noteq> 0"
  1704   unfolding of_nat_eq_0_iff by simp
  1710   unfolding of_nat_eq_0_iff by simp
  1705 
  1711 
  1706 lemma of_nat_0_neq [simp]: "0 \<noteq> of_nat (Suc n)"
  1712 lemma of_nat_0_neq [simp]: "0 \<noteq> of_nat (Suc n)"
  1707   unfolding of_nat_0_eq_iff by simp
  1713   unfolding of_nat_0_eq_iff by simp