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// RUN: %target-swift-frontend %s -emit-sil \
// RUN: -o /dev/null \
// RUN: -verify \
// RUN: -sil-verify-all \
// RUN: -module-name test \
// RUN: -enable-experimental-feature NonescapableTypes
// REQUIRES: asserts
// REQUIRES: swift_in_compiler
struct BV : ~Escapable {
let p: UnsafeRawPointer
let i: Int
@_unsafeNonescapableResult
init(_ p: UnsafeRawPointer, _ i: Int) {
self.p = p
self.i = i
}
consuming func derive() -> dependsOn(self) BV {
// Technically, this "new" view does not depend on the 'view' argument.
// This unsafely creates a new view with no dependence.
return BV(self.p, self.i)
}
}
// Nonescapable wrapper.
struct NEBV : ~Escapable {
var bv: BV
// Test lifetime inheritance through initialization.
init(_ bv: consuming BV) -> dependsOn(bv) Self {
self.bv = bv
}
var view: BV {
_read {
yield bv
}
_modify {
yield &bv
}
}
func borrowedView() -> dependsOn(scoped self) BV {
bv
}
}
// Test lifetime inheritance through chained consumes.
func bv_derive(bv: consuming BV) -> dependsOn(bv) BV {
bv.derive()
}
// Test lifetime inheritance through stored properties.
func ne_extract_member(nebv: consuming NEBV) -> dependsOn(nebv) BV {
return nebv.bv
}
func ne_yield_member(nebv: consuming NEBV) -> dependsOn(nebv) BV {
return nebv.view
}
func bv_consume(_ x: consuming BV) {}
// It is ok to consume the aggregate before the property.
// The property's lifetime must exceed the aggregate's.
func nebv_consume_member(nebv: consuming NEBV) {
let bv = nebv.bv
_ = consume nebv
bv_consume(bv)
}
func nebv_consume_after_yield(nebv: consuming NEBV) {
let view = nebv.view
_ = consume nebv
bv_consume(view)
}
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