15 lines
383 B
Text
15 lines
383 B
Text
|
import logic bool tactic
|
||
|
|
using bool eq_proofs tactic
|
||
|
|
|
||
|
|
variables a b c : bool
|
||
|
|
axiom H1 : a = b
|
||
|
|
axiom H2 : b = c
|
||
|
|
|
||
|
|
check show a = c, from H1 ⬝ H2
|
||
|
|
print "------------"
|
||
|
|
check have e1 [fact] : a = b, from H1,
|
||
|
|
have e2 : a = c, by apply trans; apply e1; apply H2,
|
||
|
|
have e3 : c = a, from e2⁻¹,
|
||
|
|
have e4 [fact] : b = a, from e1⁻¹,
|
||
|
|
show b = c, from e1⁻¹ ⬝ e2
|