??????? Perl5?е?????/???

#!/usr/bin/perl
$value = 10;
$pointer = \$value;
printf "\n Pointer Address $pointer of $value \n";
printf "\n What Pointer *($pointer) points to $$pointer\n";

Pointer Address SCALAR(0x806c520) of 10
What Pointer *(SCALAR(0x806c520)) points to 10

1  #!/usr/bin/perl
2  #
3  # Using Array references
4  #
5  $pointer = \@ARGV;
6  printf "\n Pointer Address of ARGV = $pointer\n";
7  $i = scalar(@$pointer);
8  printf "\n Number of arguments : $i \n";
9  $i = 0;
10 foreach (@$pointer) {
11   printf "$i : $$pointer[$i++]; \n";
12 }

#!/usr/bin/perl
1  #
2  # Using Associative Array references
3  #
4  %month = (
5   '01', 'Jan',
6   '02', 'Feb',
7   '03', 'Mar',
8   '04', 'Apr',
9   '05', 'May',
10  '06', 'Jun',
11  '07', 'Jul',
12  '08', 'Aug',
13  '09', 'Sep',
14  '10', 'Oct',
15  '11', 'Nov',
16  '12', 'Dec',
17  );
18
19 $pointer = \%month;
20
21 printf "\n Address of hash = $pointer\n ";
22
23 #
24 # The following lines would be used to print out the
25 # contents of the associative array if %month was used.
26 #
27 # foreach $i (sort keys %month) {
28 # printf "\n $i $$pointer{$i} ";
29 # }
30
31 #
32 # The reference to the associative array via $pointer
33 #
34 foreach $i (sort keys %$pointer) {
35   printf "$i is $$pointer{$i} \n";
36 }

$ mth
Address of hash = HASH(0x806c52c)
01 is Jan
02 is Feb
03 is Mar
04 is Apr
05 is May
06 is Jun
07 is Jul
08 is Aug
09 is Sep
10 is Oct
11 is Nov
12 is Dec

1  #!/usr/bin/perl
2  #
3  # Using Array references
4  #
5  %weekday = (
6    '01' => 'Mon',
7    '02' => 'Tue',
8    '03' => 'Wed',
9    '04' => 'Thu',
10   '05' => 'Fri',
11   '06' => 'Sat',
12   '07' => 'Sun',
13   );
14 $pointer = \%weekday;
15 $i = '05';
16 printf "\n ================== start test ================= \n";
17 #
18 # These next two lines should show an output
19 #
20   printf '$$pointer{$i} is ';
21   printf "$$pointer{$i} \n";
22   printf '${$pointer}{$i} is ';
23   printf "${$pointer}{$i} \n";
24   printf '$pointer->{$i} is ';
25
26   printf "$pointer->{$i}\n";
27 #
28 # These next two lines should not show anything 29 #
30   printf '${$pointer{$i}} is ';
31   printf "${$pointer{$i}} \n";
32   printf '${$pointer->{$i}} is ';
33   printf "${$pointer->{$i}}";
34 printf "\n ================== end of test ================= \n";
35

================== start test =================
$$pointer{$i} is Fri
${$pointer}{$i} is Fri
$pointer->{$i} is Fri
${$pointer{$i}} is
${$pointer->{$i}} is
================== end of test =================

$arrayReference->[$index]     single-dimensional array
$arrayReference->[$index1][$index2]   two-dimensional array
$arrayReference->[$index1][$index2][$index3] three-dimensional array

1  #!/usr/bin/perl
2  #
3  # Using Multi-dimensional Array references
4  #
5  $line = ['solid', 'black', ['1','2','3'] , ['4', '5', '6']];
6  print "\$line->[0] = $line->[0] \n";
7  print "\$line->[1] = $line->[1] \n";
8  print "\$line->[2][0] = $line->[2][0] \n";
9  print "\$line->[2][1] = $line->[2][1] \n";
10 print "\$line->[2][2] = $line->[2][2] \n";
11 print "\$line->[3][0] = $line->[3][0] \n";
12 print "\$line->[3][1] = $line->[3][1] \n";
13 print "\$line->[3][2] = $line->[3][2] \n";
14 print "\n"; # The obligatory output beautifier.

$line->[0] = solid
$line->[1] = black
$line->[2][0] = 1
$line->[2][1] = 2
$line->[2][2] = 3
$line->[3][0] = 4
$line->[3][1] = 5
$line->[3][2] = 6

1  #!/usr/bin/perl
2  #
3  # Using Multi-dimensional Array references again
4  #
5  $line = ['solid', 'black', ['1','2','3', ['4', '5', '6']]];
6  print "\$line->[0] = $line->[0] \n";
7  print "\$line->[1] = $line->[1] \n";
8  print "\$line->[2][0] = $line->[2][0] \n";
9  print "\$line->[2][1] = $line->[2][1] \n";
10 print "\$line->[2][2] = $line->[2][2] \n";
11 print "\$line->[2][3][0] = $line->[2][3][0] \n";
12 print "\$line->[2][3][1] = $line->[2][3][1] \n";
13 print "\$line->[2][3][2] = $line->[2][3][2] \n";
14 print "\n";

$line->[0] = solid
$line->[1] = black
$line->[2][0] = 1
$line->[2][1] = 2
$line->[2][2] = 3
$line->[2][3][0] = 4
$line->[2][3][1] = 5
$line->[2][3][2] = 6

1 #!/usr/bin/perl
2 #
3 # Using Multi-dimensional Array and Hash references
4 #
5 %cube = (
6 '0', ['0', '0', '0'],
7 '1', ['0', '0', '1'],
8 '2', ['0', '1', '0'],
9 '3', ['0', '1', '1'],
10 '4', ['1', '0', '0'],
11 '5', ['1', '0', '1'],
12 '6', ['1', '1', '0'],
13 '7', ['1', '1', '1']
14 );
15 $pointer = \%cube;
16 print "\n Da Cube \n";
17 foreach $i (sort keys %$pointer) {
18 $list = $$pointer{$i};
19 $x = $list->[0];
20 $y = $list->[1];
21 $z = $list->[2];
22 printf " Point $i = $x,$y,$z \n";
23 }

Da Cube
Point 0 = 0,0,0
Point 1 = 0,0,1
Point 2 = 0,1,0
Point 3 = 0,1,1
Point 4 = 1,0,0
Point 5 = 1,0,1
Point 6 = 1,1,0
Point 7 = 1,1,1

#!/usr/bin/perl
sub errorMsg {
  my $lvl = shift;
  #
  # define the subroutine to run when called.
  #
  return sub {
    my $msg = shift; # Define the error type now.
    print "Err Level $lvl:$msg\n"; }; # print later.
  }
$severe = errorMsg("Severe");
$fatal = errorMsg("Fatal");
$annoy = errorMsg("Annoying");

&$severe("Divide by zero");
&$fatal("Did you forget to use a semi-colon?");
&$annoy("Uninitialized variable in use");

Err Level Severe:Divide by zero
Err Level Fatal:Did you forget to use a semi-colon?
Err Level Annoying:Uninitialized variable in use

#!/usr/bin/perl
@names = (mickey, goofy, daffy );
@phones = (5551234, 5554321, 666 );
$i = 0;
sub listem {
  my ($a,$b) = @_;
  foreach (@$a) {
    print "a[$i] = " . @$a[$i] . " " . "\tb[$i] = " . @$b[$i] ."\n";
    $i++;
  }
}
&listem(\@names, \@phones);

a[0] = mickey     b[0] = 5551234
a[1] = goofy      b[1] = 5554321
a[2] = daffy      b[2] = 666

1???????????????????????????????????????????á?
2???????????????????????? (@variable)=@_; ????????????????????????в??????е?????????????С?

sub spitOut {
  my $fh = shift;
  print $fh "Gee Wilbur, I like this lettuce\n";
}

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