19 lines
341 B
Text
19 lines
341 B
Text
|
import logic
|
||
|
|
|
||
|
|
inductive sigma {A : Type} (B : A → Type) :=
|
||
|
|
mk : Π (a : A), B a → sigma B
|
||
|
|
|
||
|
|
#projections sigma :: proj1 proj2
|
||
|
|
|
||
|
|
check sigma.proj1
|
||
|
|
check sigma.proj2
|
||
|
|
|
||
|
|
variables {A : Type} {B : A → Type}
|
||
|
|
variables (a : A) (b : B a)
|
||
|
|
|
||
|
|
theorem tst1 : sigma.proj1 (sigma.mk a b) = a :=
|
||
|
|
rfl
|
||
|
|
|
||
|
|
theorem tst2 : sigma.proj2 (sigma.mk a b) = b :=
|
||
|
|
rfl
|