"m":  uint64(Minute),
	"h":  uint64(Hour),
}

// ParseDuration parses a duration string.
// A duration string is a possibly signed sequence of
// decimal numbers, each with optional fraction and a unit suffix,
// such as "300ms", "-1.5h" or "2h45m".
// Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".
func ParseDuration(s string) (Duration, error) {
	// [-+]?([0-9]*(\.[0-9]*)?[a-z]+)+

		"1.2",
		"3.14159265",
		// TODO(gri) expand
	} {
		var x Rat
		_, ok := x.SetString(want)
		if !ok {
			t.Errorf("invalid fraction %s", want)
			continue
		}
		n := max(x.Num().BitLen(), x.Denom().BitLen())

		var f1, f2 Float
		f2.SetPrec(1000)
		f1.SetRat(&x)
		f2.SetRat(&x)

		// check precision when set automatically

  }

  // Ensure that all ops are in the same region, and have the same replication
  // info.
  // TODO(bfontain): Allow for multiple regions/loops in one module.
  // TODO(patn): move this pass after cluster formation to remove the
  // complexity with replication info and metadata, cluster checking and
  // generalizing to multiple TPU clusters.
  Region* region = (*forward_pass_ops.begin())->getParentRegion();

		case syntax.IntLit, syntax.FloatLit, syntax.ImagLit:
			check.langCompat(e)
			// The max. mantissa precision for untyped numeric values
			// is 512 bits, or 4048 bits for each of the two integer
			// parts of a fraction for floating-point numbers that are
			// represented accurately in the go/constant package.
			// Constant literals that are longer than this many bits
			// are not meaningful; and excessively long constants may

    /** The per-segment table. */
    @CheckForNull volatile AtomicReferenceArray<E> table;

    /**
     * A counter of the number of reads since the last write, used to drain queues on a small
     * fraction of read operations.
     */
    final AtomicInteger readCount = new AtomicInteger();

    Segment(MapMakerInternalMap<K, V, E, S> map, int initialCapacity) {
      this.map = map;

    /** The per-segment table. */
    @CheckForNull volatile AtomicReferenceArray<E> table;

    /**
     * A counter of the number of reads since the last write, used to drain queues on a small
     * fraction of read operations.
     */
    final AtomicInteger readCount = new AtomicInteger();

    Segment(MapMakerInternalMap<K, V, E, S> map, int initialCapacity) {
      this.map = map;

			//	  print          print              print
			//
			// When -coverpkg=<pattern> is in effect, we want to
			// express the coverage percentage for each package as a
			// fraction of *all* the statements that match the
			// pattern, hence if "c" doesn't import "a", we need to
			// pass as meta-data file for "a" (emitted during the
			// package "a" build) to the package "c" run action, so