Cast of integers into fields #

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This file concerns the canonical homomorphism ℤ → F, where F is a field.

Main results #

@[norm_cast]

theorem int.cast_neg_nat_cast {R : Type u_1} [division_ring R] (n : ℕ) :

Auxiliary lemma for norm_cast to move the cast -↑n upwards to ↑-↑n.

(The restriction to division_ring is necessary, otherwise this would also apply in the case where R = ℤ and cause nontermination.)

@[simp]

theorem int.cast_div {α : Type u_1} [division_ring α] {m n : ℤ} (n_dvd : n ∣ m) (n_nonzero : ↑n ≠ 0) :