#! /usr/bin/perl -w
use strict;

my %slice;
@slice{ qw/alpha bravo/ } = ( 'foo', 'bar' );

my %assign;
$assign{alpha} = 'foo';
$assign{bravo} = 'bar';

##</code><code>##

% perl bench-hslice 100000
Benchmark: timing 100000 iterations of Assign_02, Assign_16, Assign_32, Assign_64, Slice_02, Slice_16, Slice_32, Slice_64...
 Assign_02:  1 wallclock secs ( 1.24 usr +  0.00 sys =  1.24 CPU)
 Assign_16:  7 wallclock secs ( 6.41 usr +  0.00 sys =  6.41 CPU)
 Assign_32: 14 wallclock secs (13.55 usr +  0.00 sys = 13.55 CPU)
 Assign_64: 26 wallclock secs (26.34 usr +  0.00 sys = 26.34 CPU)
  Slice_02:  2 wallclock secs ( 1.80 usr +  0.00 sys =  1.80 CPU)
  Slice_16: 10 wallclock secs ( 9.47 usr +  0.01 sys =  9.48 CPU)
  Slice_32: 19 wallclock secs (18.56 usr +  0.01 sys = 18.57 CPU)

  Slice_64: 39 wallclock secs (38.43 usr +  0.00 sys = 38.43 CPU)

##</code><code>##

  my %slice;
  @slice{ qw/alpha   bravo charlie delta/ } =
        (    $omega, $x,   $brown, $plane );

##</code><code>##

  my %slice;
  @slice{
    'alpha' = $omega,
    'bravo' = $x,
    # ...
  };

##</code><code>##

  my %slice;
  @slice{
    alpha => $omega,
    bravo => $x,
    # ...
  };

##</code><code>##

% perl bench-hslice2 100000
Benchmark: timing 100000 iterations of Assign_02, Assign_16, Assign_32, Assign_64, Slice_02, Slice_16, Slice_32, Slice_64...
 Assign_02:  1 wallclock secs ( 1.22 usr +  0.00 sys =  1.22 CPU)
 Assign_16:  7 wallclock secs ( 6.61 usr +  0.00 sys =  6.61 CPU)
 Assign_32: 13 wallclock secs (13.11 usr +  0.00 sys = 13.11 CPU)
 Assign_64: 25 wallclock secs (26.82 usr +  0.00 sys = 26.82 CPU)
  Slice_02:  0 wallclock secs ( 1.33 usr +  0.00 sys =  1.33 CPU)
  Slice_16:  7 wallclock secs ( 6.57 usr +  0.00 sys =  6.57 CPU)
  Slice_32: 13 wallclock secs (12.76 usr +  0.00 sys = 12.76 CPU)
  Slice_64: 26 wallclock secs (26.11 usr +  0.00 sys = 26.11 CPU)

##</code><code>##

% perl hslice 100000
Benchmark: timing 100000 iterations of Assign_02, Assign_16, Assign_32, Assign_64, Slice_02, Slice_16, Slice_32, Slice_64...
 Assign_02:  1 wallclock secs ( 0.68 usr +  0.00 sys =  0.68 CPU) @ 147058.82/s (n=100000)
 Assign_16:  3 wallclock secs ( 3.99 usr +  0.00 sys =  3.99 CPU) @ 25062.66/s (n=100000)
 Assign_32:  9 wallclock secs ( 8.40 usr +  0.01 sys =  8.41 CPU) @ 11890.61/s (n=100000)
 Assign_64: 17 wallclock secs (16.61 usr +  0.03 sys = 16.64 CPU) @ 6009.62/s (n=100000)
  Slice_02:  1 wallclock secs ( 0.70 usr +  0.00 sys =  0.70 CPU) @ 142857.14/s (n=100000)
  Slice_16:  4 wallclock secs ( 4.21 usr +  0.00 sys =  4.21 CPU) @ 23752.97/s (n=100000)
  Slice_32:  7 wallclock secs ( 8.30 usr +  0.00 sys =  8.30 CPU) @ 12048.19/s (n=100000)
  Slice_64: 18 wallclock secs (16.93 usr +  0.01 sys = 16.94 CPU) @ 5903.19/s (n=100000)

##</code><code>##

% cat opcode-hslice
#! /usr/bin/perl -w
use strict;
my %h;
@h{ qw/alpha bravo/ } = ( 'foo', 'bar' );

% perl -MO=Terse opcode-hslice # 5.6.1
    BINOP (0x819f8e0) aassign [2]
        UNOP (0x81b3dc0) null [141]
            OP (0x81a7868) pushmark
            SVOP (0x819c720) const  PV (0x8131440) "foo"
            SVOP (0x819c740) const  PV (0x8131434) "bar"
        UNOP (0x81b3e00) null [141]
            OP (0x81a37e8) pushmark
            LISTOP (0x8126360) hslice
                OP (0x81a7850) pushmark
                LISTOP (0x8126060) list
                    OP (0x81a79e8) pushmark
                    SVOP (0x8126240) const  PV (0x812eb8c) "alpha"
                    SVOP (0x81262a0) const  PV (0x8124224) "bravo"
                OP (0x819d128) padhv [1]

% perl -MO=Terse opcode-hslice # 5.005_03
    BINOP (0x80d4f30) pp_aassign [3]
        UNOP (0x80d4e00) pp_null [141]
            OP (0x80d4e28) pp_pushmark
            SVOP (0x8144de8) pp_const  PV (0x80d1f30) "foo"
            SVOP (0x80d4de0) pp_const  PV (0x80d1f48) "bar"
        UNOP (0x80d4ee8) pp_null [141]
            OP (0x80d4f10) pp_pushmark
            LISTOP (0x8144da0) pp_hslice
                OP (0x8144dc8) pp_pushmark
                LISTOP (0x80d5520) pp_split [2]
                    PMOP (0x81360b8) pp_pushre /\s+/
                    SVOP (0x80d54e0) pp_const  PVIV (0x80d1f90) "alpha bravo"
                    SVOP (0x80d5500) pp_const  IV (0x80d1f0c) 0
                OP (0x80d54c0) pp_padhv [1]