f.walk(ast2, ctxProg, (*File).saveExprs)

	// Accumulate exported functions.
	// The comments are only on ast1 but we need to
	// save the function bodies from ast2.
	// The first walk fills in ExpFunc, and the
	// second walk changes the entries to
	// refer to ast2 instead.
	f.walk(ast1, ctxProg, (*File).saveExport)
	f.walk(ast2, ctxProg, (*File).saveExport2)

	f.Comments = ast1.Comments

	}
	return nil
}

type (
	stringFormatter func([]byte, string)
	numberFormatter func([]byte, int64)
)

// templateV7Plus fills out the V7 fields of a block using values from hdr.
// It also fills out fields (uname, gname, devmajor, devminor) that are
// shared in the USTAR, PAX, and GNU formats using the provided formatters.
//
// The block returned is only valid until the next call to

		n = avail
		err = b.readErr()
		if err == nil {
			err = ErrBufferFull
		}
	}
	return b.buf[b.r : b.r+n], err
}

// Discard skips the next n bytes, returning the number of bytes discarded.
//
// If Discard skips fewer than n bytes, it also returns an error.
// If 0 <= n <= b.Buffered(), Discard is guaranteed to succeed without
// reading from the underlying io.Reader.

				Size:     5,
				Mode:     0640,
				Uid:      73025,
				Gid:      5000,
				Uname:    "dsymonds",
				Gname:    "eng",
				ModTime:  time.Unix(1246508266, 0),
			}, nil},
			testWrite{"Kilts", 5, nil},

			testHeader{Header{
				Typeflag: TypeReg,
				Name:     "small2.txt",
				Size:     11,
				Mode:     0640,
				Uid:      73025,
				Uname:    "dsymonds",
				Gname:    "eng",