#!./perl -w
#
# Tests derived from Japhs.
#
# These test use obscure features of Perl, or surprising combinations
# of features. The tests were added because in the past, they have
# exposed several bugs in Perl.
#
# Some of these tests may actually (mis)use bugs or use undefined behaviour.
# These tests are still useful - behavioural changes or bugfixes will be
# noted, and a remark can be put in the documentation. (Don't forget to
# disable the test!)
#
# Getting everything to run well on the myriad of platforms Perl runs on
# is unfortunately not a trivial task.
#
# WARNING: these tests are obfuscated. Do not get frustrated.
# Ask Abigail <[email protected]>, or use the Deparse or Concise
# modules (the former parses Perl to Perl, the latter shows the
# op syntax tree) like this:
# ./perl -Ilib -MO=Deparse foo.pl
# ./perl -Ilib -MO=Concise foo.pl
#
BEGIN {
if (ord("A") == 193) {
print "1..0 # Skip: EBCDIC\n"; # For now, until someone has time.
exit(0);
}
chdir 't' if -d 't';
@INC = '../lib';
require "./test.pl";
undef &skip;
}
skip_all "Unhappy on MacOS" if $^O eq 'MacOS';
#
# ./test.pl does real evilness by jumping to a label.
# This function copies the skip from ./test, omitting the goto.
#
sub skip {
my $why = shift;
my $n = @_ ? shift : 1;
for (1..$n) {
my $test = curr_test;
print STDOUT "ok $test # skip: $why\n";
next_test;
}
}
#
# ./test.pl doesn't give use 'notok', so we make it here.
#
sub notok {
my ($pass, $name, @mess) = @_;
_ok(!$pass, _where(), $name, @mess);
}
my $JaPH = "Just another Perl Hacker";
my $JaPh = "Just another Perl hacker";
my $JaPH_n = "Just another Perl Hacker\n";
my $JaPh_n = "Just another Perl hacker\n";
my $JaPH_s = "Just another Perl Hacker ";
my $JaPh_s = "Just another Perl hacker ";
my $JaPH_c = "Just another Perl Hacker,";
my $JaPh_c = "Just another Perl hacker,";
plan tests => 130;
{
my $out = sprintf "Just another Perl Hacker";
is ($out, $JaPH);
}
{
my @primes = (2, 3, 7, 13, 53, 101, 557, 1429);
my @composites = (4, 10, 25, 32, 75, 143, 1333, 1728);
my %primeness = ((map {$_ => 1} @primes),
(map {$_ => 0} @composites));
while (my ($num, $is_prime) = each %primeness) {
my $comment = "$num is " . ($is_prime ? "prime." : "composite.");
my $sub = $is_prime ? "ok" : "notok";
&$sub (( 1 x $num) !~ /^1?$|^(11+?)\1+$/, $comment);
&$sub (( 0 x $num) !~ m 0^\0?$|^(\0\0+?)\1+$0, $comment);
&$sub (("m" x $num) !~ m m^\m?$|^(\m\m+?)\1+$mm, $comment);
}
}
{ # Some platforms use different quoting techniques.
# I do not have access to those platforms to test
# things out. So, we'll skip things....
if ($^O eq 'MSWin32' ||
$^O eq 'NetWare' ||
$^O eq 'VMS') {
skip "Your platform quotes differently.", 3;
last;
}
my $expected = $JaPH;
$expected =~ s/ /\n/g;
$expected .= "\n";
is (runperl (switches => [qw /'-weprint<<EOT;' -eJust -eanother
-ePerl -eHacker -eEOT/],
verbose => 0),
$expected, "Multiple -e switches");
is (runperl (switches => [q !'-wle$_=<<EOT;y/\n/ /;print;'!,
qw ! -eJust -eanother -ePerl -eHacker -eEOT!],
verbose => 0),
$JaPH . " \n", "Multiple -e switches");
is (runperl (switches => [qw !-wl!],
progs => [qw !print qq-@{[ qw+ Just
another Perl Hacker +]}-!],
verbose => 0),
$JaPH_n, "Multiple -e switches");
}
{
if ($^O eq 'MSWin32' ||
$^O eq 'NetWare' ||
$^O eq 'VMS') {
skip "Your platform quotes differently.", 1;
last;
}
is (runperl (switches => [qw /-sweprint --/,
"-_='Just another Perl Hacker'"],
nolib => 1,
verbose => 0),
$JaPH, 'setting $_ via -s');
}
{
my $datafile = "datatmp000";
1 while -f ++ $datafile;
END {unlink_all $datafile if $datafile}
open MY_DATA, "> $datafile" or die "Failed to open $datafile: $!";
print MY_DATA << " --";
One
Two
Three
Four
Five
Six
--
close MY_DATA or die "Failed to close $datafile: $!\n";
my @progs;
my $key;
while (<DATA>) {
last if /^__END__$/;
if (/^#{7}(?:\s+(.*))?/) {
push @progs => {COMMENT => $1 || '',
CODE => '',
SKIP_OS => [],
ARGS => [],
SWITCHES => [],};
$key = 'CODE';
next;
}
elsif (/^(COMMENT|CODE|ARGS|SWITCHES|EXPECT|SKIP|SKIP_OS)
(?::\s+(.*))?$/sx) {
$key = $1;
$progs [-1] {$key} = '' unless exists $progs [-1] {$key};
next unless defined $2;
$_ = $2;
}
elsif (/^$/) {
next;
}
if (ref ($progs [-1] {$key})) {
push @{$progs [-1] {$key}} => $_;
}
else {
$progs [-1] {$key} .= $_;
}
}
foreach my $program (@progs) {
if (exists $program -> {SKIP}) {
chomp $program -> {SKIP};
skip $program -> {SKIP}, 1;
next;
}
chomp @{$program -> {SKIP_OS}};
if (@{$program -> {SKIP_OS}}) {
if (grep {$^O eq $_} @{$program -> {SKIP_OS}}) {
skip "Your OS uses different quoting.", 1;
next;
}
}
map {s/\$datafile/$datafile/} @{$program -> {ARGS}};
$program -> {EXPECT} = $JaPH unless exists $program -> {EXPECT};
$program -> {EXPECT} =~ s/\$JaPH_s\b/$JaPH_s/g;
$program -> {EXPECT} =~ s/\$JaPh_c\b/$JaPh_c/g;
$program -> {EXPECT} =~ s/\$JaPh\b/$JaPh/g;
chomp ($program -> {EXPECT}, @{$program -> {SWITCHES}},
@{$program -> {ARGS}});
fresh_perl_is ($program -> {CODE},
$program -> {EXPECT},
{switches => $program -> {SWITCHES},
args => $program -> {ARGS},
verbose => 0},
$program -> {COMMENT});
}
}
{
my $progfile = "progtmp000";
1 while -f ++ $progfile;
END {unlink_all $progfile if $progfile}
my @programs = (<< ' --', << ' --');
#!./perl
BEGIN{$|=$SIG{__WARN__}=sub{$_=$_[0];y-_- -;print/(.)"$/;seek _,-open(_
,"+<$0"),2;truncate _,tell _;close _;exec$0}}//rekcaH_lreP_rehtona_tsuJ
--
#!./perl
BEGIN{$SIG{__WARN__}=sub{$_=pop;y-_- -;print/".*(.)"/;
truncate$0,-1+-s$0;exec$0;}}//rekcaH_lreP_rehtona_tsuJ
--
chomp @programs;
if ($^O eq 'VMS') {
# VMS needs extensions for files to be executable,
# but the Japhs above rely on $0 being exactly the
# filename of the program.
skip "VMS", 2 * @programs;
last
}
use Config;
unless (defined $Config {useperlio}) {
skip "Uuseperlio", 2 * @programs;
last
}
my $i = 1;
foreach my $program (@programs) {
open my $fh => "> $progfile" or die "Failed to open $progfile: $!\n";
print $fh $program;
close $fh or die "Failed to close $progfile: $!\n";
chmod 0755 => $progfile or die "Failed to chmod $progfile: $!\n";
my $command = "./$progfile";
$command .= ' 2>&1' unless $^O eq 'MacOS';
if ( $^O eq 'qnx' ) {
skip "#!./perl not supported in QNX4";
skip "#!./perl not supported in QNX4";
} else {
my $output = `$command`;
is ($output, $JaPH, "Self correcting code $i");
$output = `$command`;
is ($output, "", "Self corrected code $i");
}
$i ++;
}
}
__END__
####### Funky loop 1.
$_ = q ;4a75737420616e6f74686572205065726c204861636b65720as;;
for (s;s;s;s;s;s;s;s;s;s;s;s)
{s;(..)s?;qq qprint chr 0x$1 and \161 ssq;excess;}
####### Funky loop 2.
$_ = q *4a75737420616e6f74686572205065726c204861636b65720a*;
for ($*=******;$**=******;$**=******) {$**=*******s*..*qq}
print chr 0x$& and q
qq}*excess********}
SKIP_OS: qnx
####### Funky loop 3.
$_ = q *4a75737420616e6f74686572205065726c204861636b65720a*;
for ($*=******;$**=******;$**=******) {$**=*******s*..*qq}
print chr 0x$& and q
qq}*excess********}
SKIP_OS: qnx
####### Funky loop 4.
$_ = q ?4a75737420616e6f74686572205065726c204861636b65720as?;??;
for (??;(??)x??;??)
{??;s;(..)s?;qq ?print chr 0x$1 and \161 ss?;excess;??}
SKIP: Abuses a fixed bug.
####### Funky loop 5.
for (s??4a75737420616e6f74686572205065726c204861636b65720as?;??;??)
{s?(..)s\??qq \?print chr 0x$1 and q ss\??excess}
SKIP: Abuses a fixed bug.
####### Funky loop 6.
$a = q 94a75737420616e6f74686572205065726c204861636b65720a9 and
${qq$\x5F$} = q 97265646f9 and s g..g;
qq e\x63\x68\x72\x20\x30\x78$&eggee;
{eval if $a =~ s e..eqq qprint chr 0x$& and \x71\x20\x71\x71qeexcess}
####### Roman Dates.
@r=reverse(M=>(0)x99=>CM=>(0)x399=>D=>(0)x99=>CD=>(
0)x299=>C=>(0)x9=>XC=>(0)x39=>L=>(0)x9=>XL=>(0)x29=>X=>IX=>0=>0=>0=>V=>IV=>0=>0
=>I=>$==-2449231+gm_julian_day+time);do{until($=<$#r){$_.=$r[$#r];$=-=$#r}for(;
!$r[--$#r];){}}while$=;$,="\x20";print+$_=>September=>MCMXCIII=>=>=>=>=>=>=>=>
SWITCHES
-MTimes::JulianDay
-l
SKIP: Times::JulianDay not part of the main distribution.
####### Autoload 1.
sub _'_{$_'_=~s/$a/$_/}map{$$_=$Z++}Y,a..z,A..X;*{($_::_=sprintf+q=%X==>"$A$Y".
"$b$r$T$u")=~s~0~O~g;map+_::_,U=>T=>L=>$Z;$_::_}=*_;sub _{print+/.*::(.*)/s};;;
*{chr($b*$e)}=*_'_;*__=*{chr(1<<$e)}; # Perl 5.6.0 broke this...
_::_(r(e(k(c(a(H(__(l(r(e(P(__(r(e(h(t(o(n(a(__(t(us(J())))))))))))))))))))))))
EXPECT: Just__another__Perl__Hacker
####### Autoload 2.
$"=$,;*{;qq{@{[(A..Z)[qq[0020191411140003]=~m[..]g]]}}}=*_=sub{print/::(.*)/};
$\=$/;q<Just another Perl Hacker>->();
####### Autoload 3.
$"=$,;*{;qq{@{[(A..Z)[qq[0020191411140003]=~m[..]g]]}}}=*_;
sub _ {push @_ => /::(.*)/s and goto &{ shift}}
sub shift {print shift; @_ and goto &{+shift}}
Hack ("Just", "Perl ", " ano", "er\n", "ther "); # YYYYMMDD
####### Autoload 4.
$, = " "; sub AUTOLOAD {($AUTOLOAD =~ /::(.*)/) [0];}
print+Just (), another (), Perl (), Hacker ();
####### Look ma! No letters!
$@="\145\143\150\157\040\042\112\165\163\164\040\141\156\157\164".
"\150\145\162\040\120\145\162\154\040\110\141\143\153\145\162".
"\042\040\076\040\057\144\145\166\057\164\164\171";`$@`
SKIP: Unix specific
####### sprintf fun 1.
sub f{sprintf$_[0],$_[1],$_[2]}print f('%c%s',74,f('%c%s',117,f('%c%s',115,f(
'%c%s',116,f('%c%s',32,f('%c%s',97,f('%c%s',0x6e,f('%c%s',111,f('%c%s',116,f(
'%c%s',104,f('%c%s',0x65,f('%c%s',114,f('%c%s',32,f('%c%s',80,f('%c%s',101,f(
'%c%s',114,f('%c%s',0x6c,f('%c%s',32,f('%c%s',0x48,f('%c%s',97,f('%c%s',99,f(
'%c%s',107,f('%c%s',101,f('%c%s',114,f('%c%s',10,)))))))))))))))))))))))))
####### sprintf fun 2.
sub f{sprintf'%c%s',$_[0],$_[1]}print f(74,f(117,f(115,f(116,f(32,f(97,
f(110,f(111,f(116,f(104,f(0x65,f(114,f(32,f(80,f(101,f(114,f(0x6c,f(32,
f(0x48,f(97,f(99,f(107,f(101,f(114,f(10,q ff)))))))))))))))))))))))))
####### Hanoi.
%0=map{local$_=$_;reverse+chop,$_}ABC,ACB,BAC,BCA,CAB,CBA;$_=3 .AC;1while+
s/(\d+)((.)(.))/($0=$1-1)?"$0$3$0{$2}1$2$0$0{$2}$4":"$3 => $4\n"/xeg;print
EXPECT
A => C
A => B
C => B
A => C
B => A
B => C
A => C
####### Funky -p 1
}{$_=$.
SWITCHES: -wlp
ARGS: $datafile
EXPECT: 6
####### Funky -p 2
}$_=$.;{
SWITCHES: -wlp
ARGS: $datafile
EXPECT: 6
####### Funky -p 3
}{$_=$.}{
SWITCHES: -wlp
ARGS: $datafile
EXPECT: 6
####### Funky -p 4
}{*_=*.}{
SWITCHES: -wlp
ARGS: $datafile
EXPECT: 6
####### Funky -p 5
}for($.){print
SWITCHES: -wln
ARGS: $datafile
EXPECT: 6
####### Funky -p 6
}{print$.
SWITCHES: -wln
ARGS: $datafile
EXPECT: 6
####### Funky -p 7
}print$.;{
SWITCHES: -wln
ARGS: $datafile
EXPECT: 6
####### Abusing -M
1
SWITCHES
-Mstrict='}); print "Just another Perl Hacker"; ({'
-l
SKIP_OS: VMS
MSWin32
NetWare
####### rand
srand 123456;$-=rand$_--=>@[[$-,$_]=@[[$_,$-]for(reverse+1..(@[=split
//=>"IGrACVGQ\x02GJCWVhP\x02PL\x02jNMP"));print+(map{$_^q^"^}@[),"\n"
SKIP: Solaris specific.
####### print and __PACKAGE__
package Just_another_Perl_Hacker; sub print {($_=$_[0])=~ s/_/ /g;
print } sub __PACKAGE__ { &
print ( __PACKAGE__)} &
__PACKAGE__
( )
####### Decorations.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
/ / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / /
% % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % %;
BEGIN {% % = ($ _ = " " => print "Just another Perl Hacker\n")}
####### Tie 1
sub J::FETCH{Just }$_.='print+"@{[map';sub J::TIESCALAR{bless\my$J,J}
sub A::FETCH{another}$_.='{tie my($x),$';sub A::TIESCALAR{bless\my$A,A}
sub P::FETCH{Perl }$_.='_;$x}qw/J A P';sub P::TIESCALAR{bless\my$P,P}
sub H::FETCH{Hacker }$_.=' H/]}\n"';eval;sub H::TIESCALAR{bless\my$H,H}
####### Tie 2
package Z;use overload'""'=>sub{$b++?Hacker:another};
sub TIESCALAR{bless\my$y=>Z}sub FETCH{$a++?Perl:Just}
$,=$";my$x=tie+my$y=>Z;print$y,$x,$y,$x,"\n";#Abigail
EXPECT: $JaPH_s
####### Tie 3
sub A::TIESCALAR{bless\my$x=>A};package B;@q[0..3]=qw/Hacker Perl
another Just/;use overload'""'=>sub{pop @q};sub A::FETCH{bless\my
$y=>B}; tie my $shoe => qq 'A';print "$shoe $shoe $shoe $shoe\n";
####### Tie 4
sub A::TIESCALAR{bless\my$x=>'A'};package B;@q=qw/Hacker Perl
another Just/;use overload'""',sub{pop @q};sub A::FETCH{bless
\my $y=>B};tie my$shoe=>'A';print"$shoe $shoe $shoe $shoe\n";
####### Tie 5
tie $" => A; $, = " "; $\ = "\n"; @a = ("") x 2; print map {"@a"} 1 .. 4;
sub A::TIESCALAR {bless \my $A => A} # Yet Another silly JAPH by Abigail
sub A::FETCH {@q = qw /Just Another Perl Hacker/ unless @q; shift @q}
SKIP: Pending a bug fix.
####### Prototype fun 1
sub camel (^#87=i@J&&&#]u'^^s]#'#={123{#}7890t[0.9]9@+*`"'***}A&&&}n2o}00}t324i;
h[{e **###{r{+P={**{e^^^#'#i@{r'^=^{l+{#}H***i[0.9]&@a5`"':&^;&^,*&^$43##@@####;
c}^^^&&&k}&&&}#=e*****[]}'r####'`=437*{#};::'1[0.9]2@43`"'*#==[[.{{],,,1278@#@);
print+((($llama=prototype'camel')=~y|+{#}$=^*&[0-9]i@:;`"',.| |d)&&$llama."\n");
SKIP: Abuses a fixed bug.
####### Prototype fun 2
print prototype sub "Just another Perl Hacker" {};
####### Prototype fun 3
sub _ "Just another Perl Hacker"; print prototype \&_
####### Split 1
split // => '"';
${"@_"} = "/"; split // => eval join "+" => 1 .. 7;
*{"@_"} = sub {foreach (sort keys %_) {print "$_ $_{$_} "}};
%{"@_"} = %_ = (Just => another => Perl => Hacker); &{%{%_}};
EXPECT: $JaPH_s
####### Split 2
$" = "/"; split // => eval join "+" => 1 .. 7;
*{"@_"} = sub {foreach (sort keys %_) {print "$_ $_{$_} "}};
%_ = (Just => another => Perl => Hacker); &{%_};
EXPECT: $JaPH_s
####### Split 3
$" = "/"; split $, => eval join "+" => 1 .. 7;
*{"@_"} = sub {foreach (sort keys %_) {print "$_ $_{$_} "}};
%{"@_"} = %_ = (Just => another => Perl => Hacker); &{%{%_}};
EXPECT: $JaPH_s
####### Here documents 1
$_ = "\x3C\x3C\x45\x4F\x54"; s/<<EOT/<<EOT/e; print;
Just another Perl Hacker
EOT
####### Here documents 2
$_ = "\x3C\x3C\x45\x4F\x54";
print if s/<<EOT/<<EOT/e;
Just another Perl Hacker
EOT
####### Here documents 3
$_ = "\x3C\x3C\x45\x4F\x54" and s/<<EOT/<<EOT/e and print;
Just another Perl Hacker
EOT
####### Here documents 4
$_ = "\x3C\x3C\x45\x4F\x54\n" and s/<<EOT/<<EOT/ee and print;
"Just another Perl Hacker"
EOT
####### Self modifying code 1
$_ = "goto F.print chop;\n=rekcaH lreP rehtona tsuJ";F1:eval
SWITCHES: -w
####### Overloaded constants 1
BEGIN {$^H {q} = sub {pop and pop and print pop}; $^H = 2**4.2**12}
"Just "; "another "; "Perl "; "Hacker";
SKIP_OS: qnx
####### Overloaded constants 2
BEGIN {$^H {q} = sub {$_ [1] =~ y/S-ZA-IK-O/q-tc-fe-m/d; $_ [1]}; $^H = 0x28100}
print "Just another PYTHON hacker\n";
EXPECT: $JaPh
####### Overloaded constants 3
BEGIN {$^H {join "" => ("a" .. "z") [8, 13, 19, 4, 6, 4, 17]} = sub
{["", "Just ", "another ", "Perl ", "Hacker\n"] -> [shift]};
$^H = hex join "" => reverse map {int ($_ / 2)} 0 .. 4}
print 1, 2, 3, 4;
####### Overloaded constants 4
BEGIN {$^H {join "" => ("a" .. "z") [8, 13, 19, 4, 6, 4, 17]} = sub
{["", "Just ", "another ", "Perl ", "Hacker"] -> [shift]};
$^H = hex join "" => reverse map {int ($_ / 2)} 0 .. 4}
print 1, 2, 3, 4, "\n";
####### Overloaded constants 5
BEGIN {my $x = "Knuth heals rare project\n";
$^H {integer} = sub {my $y = shift; $_ = substr $x => $y & 0x1F, 1;
$y > 32 ? uc : lc}; $^H = hex join "" => 2, 1, 1, 0, 0}
print 52,2,10,23,16,8,1,19,3,6,15,12,5,49,21,14,9,11,36,13,22,32,7,18,24;
####### v-strings 1
print v74.117.115.116.32;
print v97.110.111.116.104.101.114.32;
print v80.101.114.108.32;
print v72.97.99.107.101.114.10;
####### v-strings 2
print 74.117.115.116.32;
print 97.110.111.116.104.101.114.32;
print 80.101.114.108.32;
print 72.97.99.107.101.114.10;
####### v-strings 3
print v74.117.115.116.32, v97.110.111.116.104.101.114.32,
v80.101.114.108.32, v72.97.99.107.101.114.10;
####### v-strings 4
print 74.117.115.116.32, 97.110.111.116.104.101.114.32,
80.101.114.108.32, 72.97.99.107.101.114.10;
####### v-strings 5
print v74.117.115.116.32.97.110.111.116.104.101.114.
v32.80.101.114.108.32.72.97.99.107.101.114.10;
####### v-strings 6
print 74.117.115.116.32.97.110.111.116.104.101.114.
32.80.101.114.108.32.72.97.99.107.101.114.10;
####### Symbolic references.
map{${+chr}=chr}map{$_=>$_^ord$"}$=+$]..3*$=/2;
print "$J$u$s$t $a$n$o$t$h$e$r $P$e$r$l $H$a$c$k$e$r\n";
####### $; fun
$; # A lone dollar?
=$"; # Pod?
$; # The return of the lone dollar?
{Just=>another=>Perl=>Hacker=>} # Bare block?
=$/; # More pod?
print%; # No right operand for %?
####### @; fun
@;=split//=>"Joel, Preach sartre knuth\n";$;=chr 65;%;=map{$;++=>$_}
0,22,13,16,5,14,21,1,23,11,2,7,12,6,8,15,3,19,24,14,10,20,18,17,4,25
;print@;[@;{A..Z}];
EXPECT: $JaPh_c
####### %; fun
$;=$";$;{Just=>another=>Perl=>Hacker=>}=$/;print%;
####### &func;
$_ = "\112\165\163\1648\141\156\157\164\150\145\1628\120\145"
. "\162\1548\110\141\143\153\145\162\0128\177" and &japh;
sub japh {print "@_" and return if pop; split /\d/ and &japh}
####### magic goto.
sub _ {$_ = shift and y/b-yB-Y/a-yB-Y/ xor !@ _?
exit print :
print and push @_ => shift and goto &{(caller (0)) [3]}}
split // => "KsvQtbuf fbsodpmu\ni flsI " xor & _
####### $: fun 1
:$:=~s:$":Just$&another$&:;$:=~s:
:Perl$"Hacker$&:;chop$:;print$:#:
####### $: fun 2
:;$:=~s:
-:;another Perl Hacker
:;chop
$:;$:=~y
:;::d;print+Just.
$:;
####### $: fun 3
:;$:=~s:
-:;another Perl Hacker
:;chop
$:;$:=~y:;::d;print+Just.$:
####### $!
s[$,][join$,,(split$,,($!=85))[(q[0006143730380126152532042307].
q[41342211132019313505])=~m[..]g]]e and y[yIbp][HJkP] and print;
SKIP: Platform dependent.
####### die 1
eval {die ["Just another Perl Hacker"]}; print ${$@}[$#{@${@}}]
####### die 2
eval {die ["Just another Perl Hacker\n"]}; print ${$@}[$#{@${@}}]
####### die 3
eval {die ["Just another Perl Hacker"]}; print ${${@}}[$#{@{${@}}}]
####### die 4
eval {die ["Just another Perl Hacker\n"]}; print ${${@}}[$#{@{${@}}}]
####### die 5
eval {die [[qq [Just another Perl Hacker]]]};; print
${${${@}}[$#{@{${@}}}]}[$#{${@{${@}}}[$#{@{${@}}}]}]
####### Closure returning itself.
$_ = "\nrekcaH lreP rehtona tsuJ"; my $chop; $chop = sub {print chop; $chop};
$chop -> () -> () -> () -> () -> () -> () -> () -> () -> () -> () -> () -> ()
-> () -> () -> () -> () -> () -> () -> () -> () -> () -> () -> () -> () -> ()
####### Special blocks 1
BEGIN {print "Just " }
CHECK {print "another "}
INIT {print "Perl " }
END {print "Hacker\n"}
####### Special blocks 2
END {print "Hacker\n"}
INIT {print "Perl " }
CHECK {print "another "}
BEGIN {print "Just " }
####### Recursive regex.
my $qr = qr/^.+?(;).+?\1|;Just another Perl Hacker;|;.+$/;
$qr =~ s/$qr//g;
print $qr, "\n";
####### use lib 'coderef'
use lib sub {($\) = split /\./ => pop; print $"};
eval "use Just" || eval "use another" || eval "use Perl" || eval "use Hacker";
EXPECT
Just another Perl Hacker
|
