return &reader{
		Decoder: pr.TempDecoder(k, idx, marker),
		p:       pr,
	}
}

func (pr *pkgReader) retireReader(r *reader) {
	pr.RetireDecoder(&r.Decoder)
}

// @@@ Positions

func (r *reader) pos() token.Pos {
	r.Sync(pkgbits.SyncPos)
	if !r.Bool() {
		return token.NoPos
	}

	// TODO(mdempsky): Delta encoding.
	posBase := r.posBase()
	line := r.Uint()

// The supplied position is used as the position of the new value.
// Because this is used for rematerialization, check for case that (rematerialized)
// input to value with position 'pos' carried a statement mark, and that the supplied
// position (of the instruction using the rematerialized value) is not marked, and
// preserve that mark if its line matches the supplied position.

	// Base, Script, and Region methods. Once the transition is fully completed
	// the ID can be stripped from the name.

	LangID   Language
	RegionID Region
	// TODO: we will soon run out of positions for ScriptID. Idea: instead of
	// storing lang, region, and ScriptID codes, store only the compact index and
	// have a lookup table from this code to its expansion. This greatly speeds

}

// InnermostFilename returns a string containing the innermost
// (in inlining) filename at p's position
func (p *Prog) InnermostFilename() string {
	// TODO For now, this is only used for debugging output, and if we need more/better information, it might change.
	// An example of what we might want to see is the full stack of positions for inlined code, so we get some visibility into what is recorded there.
	pos := p.Ctxt.InnermostPos(p.Pos)

   * returned by {@code get(rowKeyList().get(rowIndex), columnKeyList().get(columnIndex))}, but this
   * method runs more quickly.
   *
   * @param rowIndex position of the row key in {@link #rowKeyList()}
   * @param columnIndex position of the row key in {@link #columnKeyList()}
   * @return the value with the specified row and column

	}
	if k := t.Kind_ & abi.KindMask; GOARCH != "386" && (k == abi.Float32 || k == abi.Float64) {
		// In fastcall, floating-point arguments in
		// the first four positions are passed in
		// floating-point registers, which we don't
		// currently spill. arm passes floating-point
		// arguments in VFP registers, which we also
		// don't support.
		// So basically we only support 386.

	return n
}

// setPos walks the top structure of x that has no position assigned
// and assigns it all to have position pos.
// When setPos encounters a syntax node with a position assigned,
// setPos does not look inside that node.
// setPos only needs to handle syntax we create in this package;
// all other syntax should have positions assigned already.
func setPos(x syntax.Node, pos syntax.Pos) {
	if x == nil {

  //   - 'set': `X + Y` performs a union where the array positions of all elements in `X` are preserved and
  //     non-intersecting elements in `Y` are appended, retaining their partial order.
  //   - 'map': `X + Y` performs a merge where the array positions of all keys in `X` are preserved but the values

				len(reference.Erasure.Sets[i]), len(format.Erasure.Sets[i]))
		}
		for j := range reference.Erasure.Sets[i] {
			if reference.Erasure.Sets[i][j] != format.Erasure.Sets[i][j] {
				return fmt.Errorf("UUID on positions %d:%d do not match with, expected %s got %s: (%w)",
					i, j, reference.Erasure.Sets[i][j], format.Erasure.Sets[i][j], errInconsistentDisk)
			}
		}
	}

	// Make sure that the diskID is found in the set.

   * returned by {@code get(rowKeyList().get(rowIndex), columnKeyList().get(columnIndex))}, but this
   * method runs more quickly.
   *
   * @param rowIndex position of the row key in {@link #rowKeyList()}
   * @param columnIndex position of the row key in {@link #columnKeyList()}
   * @return the value with the specified row and column