diff -r 0ec94bb9cec4 -r 1393c2340eec src/HOL/Algebra/Coset.thy --- a/src/HOL/Algebra/Coset.thy Sun Nov 26 13:19:52 2017 +0100 +++ b/src/HOL/Algebra/Coset.thy Sun Nov 26 21:08:32 2017 +0100 @@ -410,7 +410,7 @@ text\Alternative characterization of normal subgroups\ lemma (in group) normal_inv_iff: "(N \ G) = - (subgroup N G & (\x \ carrier G. \h \ N. x \ h \ (inv x) \ N))" + (subgroup N G \ (\x \ carrier G. \h \ N. x \ h \ (inv x) \ N))" (is "_ = ?rhs") proof assume N: "N \ G" @@ -476,7 +476,7 @@ assume "\h\H. y = x \ h" and x: "x \ carrier G" and sb: "subgroup H G" - then obtain h' where h': "h' \ H & x \ h' = y" by blast + then obtain h' where h': "h' \ H \ x \ h' = y" by blast show "\h\H. x = y \ h" proof show "x = y \ inv h'" using h' x sb @@ -593,7 +593,7 @@ definition r_congruent :: "[('a,'b)monoid_scheme, 'a set] \ ('a*'a)set" ("rcong\ _") - where "rcong\<^bsub>G\<^esub> H = {(x,y). x \ carrier G & y \ carrier G & inv\<^bsub>G\<^esub> x \\<^bsub>G\<^esub> y \ H}" + where "rcong\<^bsub>G\<^esub> H = {(x,y). x \ carrier G \ y \ carrier G \ inv\<^bsub>G\<^esub> x \\<^bsub>G\<^esub> y \ H}" lemma (in subgroup) equiv_rcong: @@ -784,7 +784,7 @@ lemma (in group) inj_on_f: "\H \ carrier G; a \ carrier G\ \ inj_on (\y. y \ inv a) (H #> a)" apply (rule inj_onI) -apply (subgoal_tac "x \ carrier G & y \ carrier G") +apply (subgoal_tac "x \ carrier G \ y \ carrier G") prefer 2 apply (blast intro: r_coset_subset_G [THEN subsetD]) apply (simp add: subsetD) done @@ -898,7 +898,7 @@ definition kernel :: "('a, 'm) monoid_scheme \ ('b, 'n) monoid_scheme \ ('a \ 'b) \ 'a set" \\the kernel of a homomorphism\ - where "kernel G H h = {x. x \ carrier G & h x = \\<^bsub>H\<^esub>}" + where "kernel G H h = {x. x \ carrier G \ h x = \\<^bsub>H\<^esub>}" lemma (in group_hom) subgroup_kernel: "subgroup (kernel G H h) G" apply (rule subgroup.intro)