Def x = y == (x = y  T)

is mentioned by

Thm* 'a:S, x:'a. (x = x) = true	[bequal_refl_simp]
Def b_exists_unique('a;x.p(x)) Def == (x:'a. p(x))(x,y:'a.  (p(x)p(y))(x = y))	[b_exists_unique]

In prior sections: hol hol min

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