Perl 6
Best Of Perl 6 Tablet: Revision 11
"Overview"[Perl 6 Tablets] - _Chapter:_ "0:Intr"[Perl 6 Intro Tablet], "1:Hist"[Perl 6 History Tablet], "2:Design"[Perl 6 Language Design Tablet], "3:Var"[Perl 6 Variables Tablet], "4:Op"[Perl 6 Operators Tablet], 5:IO, 6:{}, 7:Sub, 8:OOP, 9:Rx - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], *"C:Best of"[Best Of Perl 6 Tablet]*, "D:Delta"[Perl 6 Delta Tablet], "E:Links"[Perl 6 Links Tablet]
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{toc: }
This is a small tour, showing the best features and improvements of Perl 6 in short examples, compared to similar working Perl 5 examples.
^^^ Output
Making output will become simpler and easier for newbies.
| Perl 5(.8) | Perl 6 |
| print "bananas are good\n"; | say "bananas are good"; |
| print "and I said: ".$quotes{"me"}.".\n"; | say "and I said: {%quotes<me>}."; |
^^^ File IO
File::Slurp is in the Perl 6 core language and file reading is simpler then ever (and autochomp included).
| Perl 5 | Perl 6 |
| open my $FH, '<', "poetry.txt"; | $content = slurp "poetry.txt"; |
| read $FH, $content, $block_len until eof; | |
| close $FH; | |
| open my $FH, '<', "poetry.txt"; | @content = lines "poetry.txt"; |
| while (<$FH>) { chomp; push @content, $_; } | |
| close $FH; | |
^^^ Automatic multithreading
Applying operations to junctions and arrays is now syntactically compact and readable. Perl 6 will create threads where appropriate to use multiple processors, cores or hyperthreading for high level language SIMD concurrent processing.
| Perl 5 | Perl 6 |
| my $sum; | {{my $sum = [+] @numbers;}} |
| $sum += $_ for @numbers; | |
| for (0 .. $#factor1) { | {{@product = @factor1 >>*<< @factor2;}} |
| $product[$] = $factor1[$] * $factor2[$_]; | |
| } | |
The Perl 5 code is a simplification, of course Perl6 "does the right thing" when the arrays have different lengths.
^^^ Comparsion
Here are junctions, then chained comparison operators.
| Perl 5 | Perl 6 |
| {{if ($a = 3 or $a = 4 or $a = 7) {...} }} | if $a = 3 | 4 | 7 {...} |
| {{if (4 < $a and $a < 12) {...} | if 4 < $a < 12 {...} |
| if (4 < $a and $a <= 12) {...} | if $a ~~ 4^..12 {...} |
The err operator eases lot of cases where Perl 5 newbies could fall into traps.
| Perl 5 | Perl 6 |
| $a = defined $b ? $b : $c; | $a = $b // $c; |
^^^ Case construct
| Perl 5 | Perl 6 |
| {{if ($a = 2 or $a = 5) {...} }} | given $a { |
| {{elseif ($a = 6 or $a = 7 or $a = 8 or $a = 9) {...} }} | when 2 | 5 {...} |
| {{elseif ($a =~ /g/) {...} }} | when 6 .. 9 {...} |
| else {...} | when 'g' {...} |
| | default {...} |
| | } |
It's clear to read, very versatile and when used in combination with junctions, becomes even clearer.
^^^ powerful for loops
| Perl 5 | Perl 6 |
| for my $i (1..15) {...} | for 1..15 -> $i {...} |
| for (my $i=15; $i>1; $i-2) {} | {{for 1..15:by(-2)- > $i {...} }} |
| for my $key (keys %hash) { | for %hash.kv -> $key, $value { |
| print "$key => $hash{$key}\n"; ... | say "$key => $value"; ... |
| for my $i (0..$#a) { | for zip(@a; @b; @c)- > $a, $b, $c {...} |
| my $a = @a[$i]; | |
| my $b = @b[$i]; | |
| my $c = @c[$i]; | |
| ... | |
^^^ named parameters in subroutines
Perl 5:
> sub routine {
>> my $a = shift;
>> my $b = shift;
>> my @rest = @_;
> }
Perl 6:
> sub routine ($a, $b, *@rest) {...}
^^^ Objects with auto generated new and getters and setters
Simple Object creation is now as easy as it gets.
Perl 5:
> package Heart::Gold;
> sub new {
>> bless {speed => 0 }, shift;
> }
> sub speed {
>> my $self = shift;
>> my $speed = shift;
>> if (defined $speed) { $self->{speed} = $speed }
>> else { $self->{speed} }
> }
> sub stop {
>> my $self = shift;
>> $self->{speed} = 0;
> }
Perl 6:
> class Heart::Gold {
>> has $.speed;
>> method stop { $.speed = 0 }
> }
> my Heart::Gold $hg1 .= new;
> $hg1.speed = 100;
> my $hg2 = $hg1.clone;
> $hg2.speed = 50;
The new, getter, setter and clone methods are auto generated. Mthods now are called "method".
----
"Overview"[Perl 6 Tablets] - _Chapter:_ "0:Intr"[Perl 6 Intro Tablet], "1:Hist"[Perl 6 History Tablet], "2:Design"[Perl 6 Language Design Tablet], "3:Var"[Perl 6 Variables Tablet], "4:Op"[Perl 6 Operators Tablet], 5:IO, 6:{}, 7:Sub, 8:OOP, 9:Rx - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], *"C:Best of"[Best Of Perl 6 Tablet]*, "D:Delta"[Perl 6 Delta Tablet], "E:Links"[Perl 6 Links Tablet]
----
----
{toc: }
This is a small tour, showing the best features and improvements of Perl 6 in short examples, compared to similar working Perl 5 examples.
^^^ Output
Making output will become simpler and easier for newbies.
| Perl 5(.8) | Perl 6 |
| print "bananas are good\n"; | say "bananas are good"; |
| print "and I said: ".$quotes{"me"}.".\n"; | say "and I said: {%quotes<me>}."; |
^^^ File IO
File::Slurp is in the Perl 6 core language and file reading is simpler then ever (and autochomp included).
| Perl 5 | Perl 6 |
| open my $FH, '<', "poetry.txt"; | $content = slurp "poetry.txt"; |
| read $FH, $content, $block_len until eof; | |
| close $FH; | |
| open my $FH, '<', "poetry.txt"; | @content = lines "poetry.txt"; |
| while (<$FH>) { chomp; push @content, $_; } | |
| close $FH; | |
^^^ Automatic multithreading
Applying operations to junctions and arrays is now syntactically compact and readable. Perl 6 will create threads where appropriate to use multiple processors, cores or hyperthreading for high level language SIMD concurrent processing.
| Perl 5 | Perl 6 |
| my $sum; | {{my $sum = [+] @numbers;}} |
| $sum += $_ for @numbers; | |
| for (0 .. $#factor1) { | {{@product = @factor1 >>*<< @factor2;}} |
| $product[$] = $factor1[$] * $factor2[$_]; | |
| } | |
The Perl 5 code is a simplification, of course Perl6 "does the right thing" when the arrays have different lengths.
^^^ Comparsion
Here are junctions, then chained comparison operators.
| Perl 5 | Perl 6 |
| {{if ($a = 3 or $a = 4 or $a = 7) {...} }} | if $a = 3 | 4 | 7 {...} |
| {{if (4 < $a and $a < 12) {...} | if 4 < $a < 12 {...} |
| if (4 < $a and $a <= 12) {...} | if $a ~~ 4^..12 {...} |
The err operator eases lot of cases where Perl 5 newbies could fall into traps.
| Perl 5 | Perl 6 |
| $a = defined $b ? $b : $c; | $a = $b // $c; |
^^^ Case construct
| Perl 5 | Perl 6 |
| {{if ($a = 2 or $a = 5) {...} }} | given $a { |
| {{elseif ($a = 6 or $a = 7 or $a = 8 or $a = 9) {...} }} | when 2 | 5 {...} |
| {{elseif ($a =~ /g/) {...} }} | when 6 .. 9 {...} |
| else {...} | when 'g' {...} |
| | default {...} |
| | } |
It's clear to read, very versatile and when used in combination with junctions, becomes even clearer.
^^^ powerful for loops
| Perl 5 | Perl 6 |
| for my $i (1..15) {...} | for 1..15 -> $i {...} |
| for (my $i=15; $i>1; $i-2) {} | {{for 1..15:by(-2)- > $i {...} }} |
| for my $key (keys %hash) { | for %hash.kv -> $key, $value { |
| print "$key => $hash{$key}\n"; ... | say "$key => $value"; ... |
| for my $i (0..$#a) { | for zip(@a; @b; @c)- > $a, $b, $c {...} |
| my $a = @a[$i]; | |
| my $b = @b[$i]; | |
| my $c = @c[$i]; | |
| ... | |
^^^ named parameters in subroutines
Perl 5:
> sub routine {
>> my $a = shift;
>> my $b = shift;
>> my @rest = @_;
> }
Perl 6:
> sub routine ($a, $b, *@rest) {...}
^^^ Objects with auto generated new and getters and setters
Simple Object creation is now as easy as it gets.
Perl 5:
> package Heart::Gold;
> sub new {
>> bless {speed => 0 }, shift;
> }
> sub speed {
>> my $self = shift;
>> my $speed = shift;
>> if (defined $speed) { $self->{speed} = $speed }
>> else { $self->{speed} }
> }
> sub stop {
>> my $self = shift;
>> $self->{speed} = 0;
> }
Perl 6:
> class Heart::Gold {
>> has $.speed;
>> method stop { $.speed = 0 }
> }
> my Heart::Gold $hg1 .= new;
> $hg1.speed = 100;
> my $hg2 = $hg1.clone;
> $hg2.speed = 50;
The new, getter, setter and clone methods are auto generated. Mthods now are called "method".
----
"Overview"[Perl 6 Tablets] - _Chapter:_ "0:Intr"[Perl 6 Intro Tablet], "1:Hist"[Perl 6 History Tablet], "2:Design"[Perl 6 Language Design Tablet], "3:Var"[Perl 6 Variables Tablet], "4:Op"[Perl 6 Operators Tablet], 5:IO, 6:{}, 7:Sub, 8:OOP, 9:Rx - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], *"C:Best of"[Best Of Perl 6 Tablet]*, "D:Delta"[Perl 6 Delta Tablet], "E:Links"[Perl 6 Links Tablet]
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