Go1_21 = "go1.21"
	Go1_22 = "go1.22"
)

// Future is an invalid unknown Go version sometime in the future.
// Do not use directly with Compare.
const Future = ""

// AtLeast reports whether the file version v comes after a Go release.
//
// Use this predicate to enable a behavior once a certain Go release
// has happened (and stays enabled in the future).
func AtLeast(v, release string) bool {
	if v == Future {

# the go.mod file to record a specific, stable toolchain version that can.

! go mod verify
stderr '^go: rsc.io/future@v1.0.0: module rsc.io/future@v1.0.0 requires go >= 1.999 \(running go 1.21.0\)'

! go mod graph
stderr '^go: rsc.io/future@v1.0.0: module rsc.io/future@v1.0.0 requires go >= 1.999 \(running go 1.21.0\)'

# TODO(#64008): 'go mod download' without arguments should fail too.

rsc.io/future v1.0.0
written by hand

-- .mod --
module rsc.io/future
go 1.999
-- .info --
{"Version":"v1.0.0"}
-- main.go --
package main

func main() {
}
-- go.mod --
module rsc.io/future

// license that can be found in the LICENSE file.

// Linkname fastrand is allowed _for now_, as it has a
// linknamed definition, for legacy reason.
// NOTE: this may not be allowed in the future. Don't do this!

package main

import _ "unsafe"

//go:linkname fastrand runtime.fastrand
func fastrand() uint32

func main() {
	println(fastrand())

	if err != nil {
		return err
	}
	flagsPtr, err := BytePtrFromString(flags)
	if err != nil {
		return err
	}
	return unveil(pathPtr, flagsPtr)
}

// UnveilBlock blocks future unveil calls.
// For more information see unveil(2).
func UnveilBlock() error {
	if err := supportsUnveil(); err != nil {
		return err
	}
	return unveil(nil, nil)
}

transfer and otherwise run, modify and propagate the contents of this
implementation of Go, where such license applies only to those patent
claims, both currently owned or controlled by Google and acquired in
the future, licensable by Google that are necessarily infringed by this
implementation of Go.  This grant does not include claims that would be
infringed only as a consequence of further modification of this

transfer and otherwise run, modify and propagate the contents of this
implementation of Go, where such license applies only to those patent
claims, both currently owned or controlled by Google and acquired in
the future, licensable by Google that are necessarily infringed by this
implementation of Go.  This grant does not include claims that would be
infringed only as a consequence of further modification of this

					diffJSON(t, buf.Bytes(), want)
				})
			}
		})
	}
}

// writeAndKill writes b to w and then fills b with Zs.
// The filling makes sure that if w is holding onto b for
// future use, that future use will have obviously wrong data.
func writeAndKill(w io.Writer, b []byte) {
	w.Write(b)
	for i := range b {
		b[i] = 'Z'
	}
}

// diffJSON diffs the stream we have against the stream we want

	// Length of the meta-data.
	MetaLen int

	// Hash computed by cmd/cover of the meta-data.
	MetaHash string

	// Instrumentation strategy. For now this is always set to
	// "normal", but in the future we may add new values (for example,
	// if panic paths are instrumented, or if the instrumenter
	// eliminates redundant counters).
	Strategy string

	// Prefix assigned to the names of counter variables generated

				// and other terms and the result would not be
				// in normal form.)
				if u1.typ == nil {
					return allTermlist
				}
				xi = u1
				used[j] = true // xj is now unioned into xi - ignore it in future iterations
			}
		}
		rl = append(rl, xi)
	}
	return rl
}

// union returns the union xl ∪ yl.
func (xl termlist) union(yl termlist) termlist {
	return append(xl, yl...).norm()
}