view src/agda-term1.agda.replaced @ 1:73127e0ab57c

(none)
author soto@cr.ie.u-ryukyu.ac.jp
date Tue, 08 Sep 2020 18:38:08 +0900
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+-comm : (x y : @$\mathbb{N}$@) @$\rightarrow$@ x + y @$\equiv$@ y + x
+-comm zero y rewrite (+zero {y}) = refl
+-comm (suc x) y = let open @$\equiv$@-Reasoning in
  begin
  ?0 @$\equiv$@@$\langle$@ ?1 @$\rangle$@
  ?2 @$\blacksquare$@

-- ?0 : @$\mathbb{N}$@ {(suc x) + y}
-- ?1 : suc x + y @$\equiv$@ y + suc x
-- ?2 : @$\mathbb{N}$@