4f2e0c6d7f
The new command provides a uniform way to set declaration attributes. It replaces the commands: class, instance, coercion, multiple_instances, reducible, irreducible
43 lines
918 B
Text
43 lines
918 B
Text
prelude
|
|
precedence `+`:65
|
|
|
|
namespace nat
|
|
constant nat : Type.{1}
|
|
constant add : nat → nat → nat
|
|
infixl + := add
|
|
end nat
|
|
|
|
namespace int
|
|
open nat (nat)
|
|
constant int : Type.{1}
|
|
constant add : int → int → int
|
|
infixl + := add
|
|
constant of_nat : nat → int
|
|
attribute of_nat [coercion]
|
|
end int
|
|
|
|
section
|
|
-- Open "only" the notation and declarations from the namespaces nat and int
|
|
open [notations] nat
|
|
open [notations] int
|
|
open [decls] nat
|
|
open [decls] int
|
|
|
|
variables n m : nat
|
|
variables i j : int
|
|
check n + m
|
|
check i + j
|
|
|
|
-- The following check does not work, since we are not open the coercions
|
|
-- check n + i
|
|
|
|
-- Here is a possible trick for this kind of configuration
|
|
definition add_ni (a : nat) (b : int) := (of_nat a) + b
|
|
definition add_in (a : int) (b : nat) := a + (of_nat b)
|
|
infixl + := add_ni
|
|
infixl + := add_in
|
|
check add_ni
|
|
|
|
check i + n
|
|
check n + i
|
|
end
|