type scriptedReader []func(p []byte) (n int, err error)

func (sr *scriptedReader) Read(p []byte) (n int, err error) {
	if len(*sr) == 0 {
		panic("too many Read calls on scripted Reader. No steps remain.")
	}
	step := (*sr)[0]
	*sr = (*sr)[1:]
	return step(p)
}

func newScriptedReader(steps ...func(p []byte) (n int, err error)) io.Reader {
	sr := scriptedReader(steps)
	return &sr
}

If the type is omitted, the constants take the
individual types of the corresponding expressions.
If the expression values are untyped <a href="#Constants">constants</a>,
the declared constants remain untyped and the constant identifiers
denote the constant values. For instance, if the expression is a
floating-point literal, the constant identifier denotes a floating-point

			}

			uint16string := strings.Repeat(".", uint16max)
			remain := wantLen
			for remain > 0 {
				commentLen := int(uint16max) - directoryHeaderLen - 1
				thisRecLen := directoryHeaderLen + int(uint16max) + commentLen
				if int64(thisRecLen) > remain {
					remove := thisRecLen - int(remain)
					commentLen -= remove
					thisRecLen -= remove
				}
				remain -= int64(thisRecLen)
				f, err := w.CreateHeader(&FileHeader{

These new behaviors are only enabled when the main Go program
is in a module with a `go.mod` `go` line using Go 1.23.0 or later.
When Go 1.23 builds older programs, the old behaviors remain in effect.
The new [GODEBUG setting](/doc/godebug) [`asynctimerchan=1`](/pkg/time/#NewTimer)
can be used to revert back to asynchronous channel behaviors

		if p.arch.InFamily(sys.ARM, sys.ARM64) {
			// Special form
			// ARM: destination register pair (R1, R2).
			// ARM64: register pair (R1, R2) for LDP/STP.
			if prefix != 0 || scale != 0 {
				p.errorf("illegal address mode for register pair")
				return
			}
			a.Type = obj.TYPE_REGREG
			a.Offset = int64(r2)
			// Nothing may follow
			return
		}

corresponding type parameters have corresponding constraints.
</p>

<pre>
type Pair[A, B any] struct {
	a A
	b B
}

func (p Pair[A, B]) Swap() Pair[B, A]  { … }  // receiver declares A, B
func (p Pair[First, _]) First() First  { … }  // receiver declares First, corresponds to A in Pair
</pre>

<h2 id="Expressions">Expressions</h2>

<p>

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

package p4

type Pair[T1 interface{ M() }, T2 ~int] struct {
	f1 T1
	f2 T2
}

func NewPair[T1 interface{ M() }, T2 ~int](v1 T1, v2 T2) Pair[T1, T2] {
	return Pair[T1, T2]{f1: v1, f2: v2}
}

func (p Pair[X1, _]) First() X1 {
	return p.f1
}

func (p Pair[_, X2]) Second() X2 {
	return p.f2
}

// Deprecated: Use something else.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer

pkg p4, func NewPair[$0 interface{ M }, $1 interface{ ~int }]($0, $1) Pair[$0, $1]
pkg p4, method (Pair[$0, $1]) Second() $1
pkg p4, method (Pair[$0, $1]) First() $0
pkg p4, type Pair[$0 interface{ M }, $1 interface{ ~int }] struct
pkg p4, func Clone[$0 interface{ ~[]$1 }, $1 interface{}]($0) $0

		return
	}

	b.lastByte = -1
	b.lastRuneSize = -1

	remain := n
	for {
		skip := b.Buffered()
		if skip == 0 {
			b.fill()
			skip = b.Buffered()
		}
		if skip > remain {
			skip = remain
		}
		b.r += skip
		remain -= skip
		if remain == 0 {
			return n, nil
		}
		if b.err != nil {
			return n - remain, b.readErr()
		}
	}
}

// Read reads data into p.