Calls.proof: def of bolt@1.27.0.0
Import: import bolt@1.27.0.0/src/rules/calls.bend as Calls
Lines 289-293 of bolt@1.27.0.0/src/rules/calls.bend: https://jend.leeeet.dev/read.txt?path=bolt@1.27.0.0/src/rules/calls.bend&start_line=289&end_line=293

import Base
import bolt@1.27.0.0/src/syntax/tree.bend as Tree

# is the def a proof? One that returns a proof (`-> {a == b : T}`), or one
# written with no type at all (`def f(x, y):`), which is how Bend fills the
# law named f
def proof(+sig: Tree.Node) -> Bool:
  Bool.or(returns_proof(sig), Bool.not(typed(sig)))

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.not
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.or
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/calls.bend&name=returns_proof
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/calls.bend&name=typed
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/tree.bend&name=Node