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 Perl7::Handy à¦à¦¿à¦ à¦¶à¦¿à¦                   [BN] à¦¬à¦¾à¦à¦²à¦¾
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[ 1. Installation ]

  à¦à¦¨à¦¸à§à¦à¦² à¦à¦°à§à¦¨:
    cpan Perl7::Handy

  à¦¸à§à¦à§à¦°à¦¿à¦ªà§à¦à§ à¦¬à§à¦¯à¦¬à¦¹à¦¾à¦°:
    use Perl7::Handy;

  à¦ªà§à¦°à¦­à¦¾à¦¬ (Perl 5.010001 à¦à¦¬à¦ à¦ªà¦°à¦¬à¦°à§à¦¤à§):
    * use strict               -- à¦à¦²à¦ à¦à§à¦·à¦£à¦¾ à¦¬à¦¾à¦§à§à¦¯à¦¤à¦¾à¦®à§à¦²à¦ à¦à¦°à§
    * use warnings             -- à¦¸à¦¤à¦°à§à¦à¦¤à¦¾ à¦¸à¦à§à¦°à¦¿à¦¯à¦¼ à¦à¦°à§
    * no bareword::filehandles -- open(FILE,...) à¦¶à§à¦²à§ à¦ªà§à¦°à¦¤à§à¦¯à¦¾à¦à§à¦¯à¦¾à¦¨ à¦à¦°à§
    * no multidimensional      -- $hash{a,b} à¦à¦¨à§à¦à¦°à¦£ à¦¨à¦¿à¦·à§à¦à§à¦°à¦¿à¦¯à¦¼ à¦à¦°à§
    * use feature qw(signatures)  (Perl 5.020+)
    * no feature qw(indirect)     (Perl 5.031009+)

  à¦ªà§à¦°à¦­à¦¾à¦¬ (Perl 5.005_03 -- 5.008):
    * use strict
    * open/opendir/sysopen/pipe/socket/accept à¦à¦à§à¦­à¦¿à¦­à¦¿à¦«à¦¿à¦à§à¦¶à¦¨
    # socket() ব্যর্থতায় autodie করে না (void context-এ false ফেরত দেয়)
    * tie à¦­à¦¿à¦¤à§à¦¤à¦¿à¦ $; à¦«à¦¾à¦à¦¦ (à¦¬à¦¹à§à¦®à¦¾à¦¤à§à¦°à¦¿à¦ à¦à§à¦¯à¦¾à¦°à§ à¦à¦¨à§à¦à¦°à¦£ à¦°à§à¦§)

[ 2. open() -- autovivification ]

  my $fh;
  open($fh, "< file.txt");   # à¦ªà¦¡à¦¼à§à¦¨
  open($fh, "> file.txt");   # à¦²à¦¿à¦à§à¦¨ (à¦à¦­à¦¾à¦°à¦°à¦¾à¦à¦)
  open($fh, ">> file.txt");  # à¦¯à§à¦ à¦à¦°à§à¦¨
  open($fh, "+< file.txt");  # à¦ªà¦¡à¦¼à§à¦¨/à¦²à¦¿à¦à§à¦¨
  while (my $line = readline($fh)) { ... }
  print $fh "text\n";
  close($fh);

  # bareword à¦¹à§à¦¯à¦¾à¦¨à§à¦¡à§à¦² à¦ªà§à¦°à¦¤à§à¦¯à¦¾à¦à§à¦¯à¦¾à¦¤:
  open(FILE, "< file.txt");   # dies: Use of bareword handle in open

[ 3. open() -- 3-arg ]

  my $fh;
  open($fh, '<',  "file.txt");   # à¦ªà¦¡à¦¼à§à¦¨
  open($fh, '>',  "file.txt");   # à¦²à¦¿à¦à§à¦¨ (à¦à¦­à¦¾à¦°à¦°à¦¾à¦à¦)
  open($fh, '>>', "file.txt");   # à¦¯à§à¦ à¦à¦°à§à¦¨
  open($fh, '+<', "file.txt");   # à¦ªà¦¡à¦¼à§à¦¨/à¦²à¦¿à¦à§à¦¨
  open($fh, '+>', "file.txt");   # à¦ªà¦¡à¦¼à§à¦¨/à¦²à¦¿à¦à§à¦¨ (à¦à¦­à¦¾à¦°à¦°à¦¾à¦à¦)
  open($fh, '-|', "cmd");        # à¦à¦®à¦¾à¦¨à§à¦¡ à¦ªà¦¾à¦à¦ª à¦¥à§à¦à§ à¦ªà¦¡à¦¼à§à¦¨
  open($fh, '|-', "cmd");        # à¦à¦®à¦¾à¦¨à§à¦¡ à¦ªà¦¾à¦à¦ªà§ à¦²à¦¿à¦à§à¦¨

[ 4. opendir() / sysopen() ]

  my $dh;
  opendir($dh, "/path/to/dir");
  while (my $e = readdir($dh)) {
      next if $e eq '.' or $e eq '..';
      print "$e\n";
  }
  closedir($dh);

  use Fcntl qw(O_RDONLY O_WRONLY O_CREAT O_TRUNC);
  my $fh;
  sysopen($fh, "file.txt", O_RDONLY);
  sysopen($fh, "file.txt", O_WRONLY | O_CREAT | O_TRUNC, 0644);

[ 5. pipe() ]

  my($reader, $writer);
  pipe($reader, $writer);
  if (my $pid = fork()) {
      close($writer);
      while (my $line = readline($reader)) { print $line }
      close($reader);
  } else {
      close($reader);
      print $writer "à¦¶à¦¿à¦¶à§ à¦ªà§à¦°à¦à§à¦°à¦¿à¦¯à¦¼à¦¾ à¦¥à§à¦à§ à¦¹à§à¦¯à¦¾à¦²à§\n";
      close($writer);
      exit 0;
  }

[ 6. socket() / accept() ]

  use Socket qw(AF_INET SOCK_STREAM sockaddr_in inet_aton);
  my $server;
  socket($server, AF_INET, SOCK_STREAM, 0);
  # নোট: socket() ব্যর্থতায় autodie করে না; রিটার্ন ভ্যালু স্পষ্টভাবে পরীক্ষা করুন।
  my $client;
  accept($client, $server);

[ 7. no bareword::filehandles ]

  # bareword à¦¹à§à¦¯à¦¾à¦¨à§à¦¡à§à¦² à¦ªà§à¦°à¦¤à§à¦¯à¦¾à¦à§à¦¯à¦¾à¦¤:
  open(FILE, "< file.txt");    # error: Bareword filehandle
  print FILE "hello\n";        # error: Bareword filehandle

  # à¦²à§à¦à§à¦¸à¦¿à¦à§à¦¯à¦¾à¦² à¦­à§à¦°à¦¿à¦¯à¦¼à§à¦¬à¦² à¦¬à§à¦¯à¦¬à¦¹à¦¾à¦° à¦à¦°à§à¦¨:
  my $fh;
  open($fh, "< file.txt");
  print $fh "hello\n";
  close($fh);

[ 8. no multidimensional ]

  # à¦¬à¦¹à§à¦®à¦¾à¦¤à§à¦°à¦¿à¦ à¦¹à§à¦¯à¦¾à¦¶ à¦à¦¨à§à¦à¦°à¦£ à¦¨à¦¿à¦·à§à¦à§à¦°à¦¿à¦¯à¦¼:
  my %h;
  $h{1,2} = "val";    # error: Use of multidimensional array emulation

  # à¦¸à§à¦ªà¦·à§à¦ à¦à§ à¦¬à§à¦¯à¦¬à¦¹à¦¾à¦° à¦à¦°à§à¦¨:
  $h{"$x,$y"} = "val";

[ 9. Signatures (Perl 5.020+) ]

  # à¦¸à¦¿à¦à¦¨à§à¦à¦¾à¦° à¦¸à§à¦¬à¦¯à¦¼à¦à¦à§à¦°à¦¿à¦¯à¦¼à¦­à¦¾à¦¬à§ à¦¸à¦à§à¦°à¦¿à¦¯à¦¼; à¦ªà¦°à§à¦à§à¦·à¦¾à¦®à§à¦²à¦ à¦¸à¦¤à¦°à§à¦à¦¤à¦¾ à¦¦à¦®à¦¿à¦¤
  use Perl7::Handy;

  sub greet($name) { return "Hello, $name!" }
  sub add($x, $y)  { return $x + $y }

[ 10. no indirect (Perl 5.031009+) ]

  # à¦ªà¦°à§à¦à§à¦· à¦à¦¬à¦à§à¦à§à¦ à¦¸à¦¿à¦¨à¦à§à¦¯à¦¾à¦à§à¦¸ à¦¨à¦¿à¦·à§à¦à§à¦°à¦¿à¦¯à¦¼:
  my $obj = new MyClass;   # error: indirect syntax

  # à¦¸à¦°à¦¾à¦¸à¦°à¦¿ à¦¸à¦¿à¦¨à¦à§à¦¯à¦¾à¦à§à¦¸ à¦¬à§à¦¯à¦¬à¦¹à¦¾à¦° à¦à¦°à§à¦¨:
  my $obj = MyClass->new;

[ 11. CVE-2016-1238 ]

  # Perl7::Handy à¦¸à§à¦à¦¾à¦°à§à¦à¦à¦ªà§ @INC à¦¥à§à¦à§ à¦¬à¦°à§à¦¤à¦®à¦¾à¦¨ à¦¡à¦¿à¦°à§à¦à§à¦à¦°à¦¿ à¦¸à¦°à¦¿à¦¯à¦¼à§ à¦¦à§à¦¯à¦¼à¥¤
  # BEGIN { pop @INC if $INC[-1] eq '.' }

[ 12. à¦¸à¦à¦¸à§à¦à¦°à¦£ à¦¸à¦¾à¦®à¦à§à¦à¦¸à§à¦¯ à¦®à§à¦¯à¦¾à¦à§à¦°à¦¿à¦à§à¦¸ ]

  Feature              5.005_03  5.006-009  5.010+  5.020+  5.031009+
  -------------------  --------  ---------  ------  ------  ---------
  strict               yes       yes        yes     yes     yes
  warnings             no        yes        yes     yes     yes
  autovivif. open()    yes       yes        yes*    yes*    yes*
  no bareword FH       emulated  emulated   yes     yes     yes
  no multidim.         tie       tie        yes     yes     yes
  signatures           no        no         no      yes     yes
  no indirect          no        no         no      no      yes

[ 13. Official resources ]

  Perl7::Handy (MetaCPAN):
    https://metacpan.org/dist/Perl7-Handy

  bareword::filehandles:
    https://metacpan.org/dist/bareword-filehandles

  INABA Hitoshi (ina) on CPAN:
    https://metacpan.org/author/INA

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