lean2/tests/lean/run/rewriter6.lean
2015-03-27 17:54:48 -07:00

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Text

import data.int
open int
theorem abs_thm1 (a b : int) : a - b = a + -b :=
by rewrite ↑sub -- unfold sub
theorem abs_thm2 (a b : int) : a - b = a + -b :=
by rewrite ^sub -- unfold sub
definition double (x : int) := x + x
theorem double_zero (x : int) : double (0 + x) = (1 + 1)*x :=
by rewrite [↑double, zero_add, mul.right_distrib, one_mul]