src/Sequents/LK/Nat.thy
changeset 61386 0a29a984a91b
parent 61385 538100cc4399
equal deleted inserted replaced
61385:538100cc4399 61386:0a29a984a91b
    15 axiomatization
    15 axiomatization
    16   Zero :: nat      ("0") and
    16   Zero :: nat      ("0") and
    17   Suc :: "nat \<Rightarrow> nat" and
    17   Suc :: "nat \<Rightarrow> nat" and
    18   rec :: "[nat, 'a, [nat,'a] \<Rightarrow> 'a] \<Rightarrow> 'a"
    18   rec :: "[nat, 'a, [nat,'a] \<Rightarrow> 'a] \<Rightarrow> 'a"
    19 where
    19 where
    20   induct:  "\<lbrakk>$H |- $E, P(0), $F;
    20   induct:  "\<lbrakk>$H \<turnstile> $E, P(0), $F;
    21              \<And>x. $H, P(x) |- $E, P(Suc(x)), $F\<rbrakk> \<Longrightarrow> $H |- $E, P(n), $F" and
    21              \<And>x. $H, P(x) \<turnstile> $E, P(Suc(x)), $F\<rbrakk> \<Longrightarrow> $H \<turnstile> $E, P(n), $F" and
    22 
    22 
    23   Suc_inject:  "|- Suc(m) = Suc(n) \<longrightarrow> m = n" and
    23   Suc_inject:  "\<turnstile> Suc(m) = Suc(n) \<longrightarrow> m = n" and
    24   Suc_neq_0:   "|- Suc(m) \<noteq> 0" and
    24   Suc_neq_0:   "\<turnstile> Suc(m) \<noteq> 0" and
    25   rec_0:       "|- rec(0,a,f) = a" and
    25   rec_0:       "\<turnstile> rec(0,a,f) = a" and
    26   rec_Suc:     "|- rec(Suc(m), a, f) = f(m, rec(m,a,f))"
    26   rec_Suc:     "\<turnstile> rec(Suc(m), a, f) = f(m, rec(m,a,f))"
    27 
    27 
    28 definition add :: "[nat, nat] \<Rightarrow> nat"  (infixl "+" 60)
    28 definition add :: "[nat, nat] \<Rightarrow> nat"  (infixl "+" 60)
    29   where "m + n == rec(m, n, \<lambda>x y. Suc(y))"
    29   where "m + n == rec(m, n, \<lambda>x y. Suc(y))"
    30 
    30 
    31 
    31 
    32 declare Suc_neq_0 [simp]
    32 declare Suc_neq_0 [simp]
    33 
    33 
    34 lemma Suc_inject_rule: "$H, $G, m = n |- $E \<Longrightarrow> $H, Suc(m) = Suc(n), $G |- $E"
    34 lemma Suc_inject_rule: "$H, $G, m = n \<turnstile> $E \<Longrightarrow> $H, Suc(m) = Suc(n), $G \<turnstile> $E"
    35   by (rule L_of_imp [OF Suc_inject])
    35   by (rule L_of_imp [OF Suc_inject])
    36 
    36 
    37 lemma Suc_n_not_n: "|- Suc(k) \<noteq> k"
    37 lemma Suc_n_not_n: "\<turnstile> Suc(k) \<noteq> k"
    38   apply (rule_tac n = k in induct)
    38   apply (rule_tac n = k in induct)
    39   apply simp
    39   apply simp
    40   apply (fast add!: Suc_inject_rule)
    40   apply (fast add!: Suc_inject_rule)
    41   done
    41   done
    42 
    42 
    43 lemma add_0: "|- 0 + n = n"
    43 lemma add_0: "\<turnstile> 0 + n = n"
    44   apply (unfold add_def)
    44   apply (unfold add_def)
    45   apply (rule rec_0)
    45   apply (rule rec_0)
    46   done
    46   done
    47 
    47 
    48 lemma add_Suc: "|- Suc(m) + n = Suc(m + n)"
    48 lemma add_Suc: "\<turnstile> Suc(m) + n = Suc(m + n)"
    49   apply (unfold add_def)
    49   apply (unfold add_def)
    50   apply (rule rec_Suc)
    50   apply (rule rec_Suc)
    51   done
    51   done
    52 
    52 
    53 declare add_0 [simp] add_Suc [simp]
    53 declare add_0 [simp] add_Suc [simp]
    54 
    54 
    55 lemma add_assoc: "|- (k + m) + n = k + (m + n)"
    55 lemma add_assoc: "\<turnstile> (k + m) + n = k + (m + n)"
    56   apply (rule_tac n = "k" in induct)
    56   apply (rule_tac n = "k" in induct)
    57   apply simp_all
    57   apply simp_all
    58   done
    58   done
    59 
    59 
    60 lemma add_0_right: "|- m + 0 = m"
    60 lemma add_0_right: "\<turnstile> m + 0 = m"
    61   apply (rule_tac n = "m" in induct)
    61   apply (rule_tac n = "m" in induct)
    62   apply simp_all
    62   apply simp_all
    63   done
    63   done
    64 
    64 
    65 lemma add_Suc_right: "|- m + Suc(n) = Suc(m + n)"
    65 lemma add_Suc_right: "\<turnstile> m + Suc(n) = Suc(m + n)"
    66   apply (rule_tac n = "m" in induct)
    66   apply (rule_tac n = "m" in induct)
    67   apply simp_all
    67   apply simp_all
    68   done
    68   done
    69 
    69 
    70 lemma "(\<And>n. |- f(Suc(n)) = Suc(f(n))) \<Longrightarrow> |- f(i + j) = i + f(j)"
    70 lemma "(\<And>n. \<turnstile> f(Suc(n)) = Suc(f(n))) \<Longrightarrow> \<turnstile> f(i + j) = i + f(j)"
    71   apply (rule_tac n = "i" in induct)
    71   apply (rule_tac n = "i" in induct)
    72   apply simp_all
    72   apply simp_all
    73   done
    73   done
    74 
    74 
    75 end
    75 end