Perl 6
Perl 6 Operator Tablet: Revision 32
"Overview"[Perl 6 Tablets] - _Chapter:_ "0:History"[Perl 6 History Tablet], "1:Design"[Perl 6 Language Design Tablet], "2:Basics"[Perl 6 Basics Tablet], "3:Var"[Perl 6 Variable Tablet], *"4:Op"[Perl 6 Operator Tablet]*, "5:IO"[Perl 6 IO Tablet], "6:{}"[Perl 6 Block Tablet], "7:Sub"[Perl 6 Subroutine Tablet], "8:OOP"[Perl 6 OOP Tablet], "9:Rx"[Perl 6 Regex Tablet], "10:Meta"[Perl 6 Meta Tablet]
"Intro"[Perl 6 Intro Tablet] - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], "C:Cook"[Perl 6 Cookbook Tablet], "D:Delta"[Perl 6 Delta Tablet], "E:Best of"[Best Of Perl 6 Tablet], "F:Links"[Perl 6 Links Tablet]
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{toc: }
_Perl folklore: Perl is an operator based language._
Perl 6 has a huge amount of operators, because they support 2 of the main design goals: they offer *dense* and *readable* code. _{{2 + 3}}_ is certainly shorter and easier to understand then _{{add(2,3)}}_, since "pictograms"{link: [perl 6 language design tablet] visual metaphor} can be picked up faster than words. (Fortran made his whole carrier on that). But because they are so many, they had to be sorted by a rule named "huffman coding"{link: [perl 6 language design tablet] huffman coding}, which was applied here more than in any other part of the syntax.
To understand an operator you have to know his *arity* (how many parameters he takes - usually one (!) or two (+) ).
The *"precedence"{link: [perl 6 lookup tablet]table of precedence}* tells which operator to prefer in case of conflict, when no braces are used (round braces are only used for grouping and managing precedence). It allows _{{2 + 3 * 5}}_ to return 17, not 25, which would upset your math teacher.
Behind that link is a table which also tells you also the *"associativity"{link: [perl 6 lookup tablet]Operator Associativity}* of every operator. This tells you after which rule to resolve precedence if one operator is used several times like in _{{2 * 3 * 7}}_.
^ Comparison
^^ Smartmatch
This is the most mighty (much more mighty than its backported Perl 5 twin) of all Perl 6 operators. It can be called the {{"compare-this-with-that-operator"}}. If the left side of that infix op matches somehow the content of the right side, it returns Bool::True, otherwise Bool::False. The negated form *!~* naturally works the other way around. The exact comparison operation depends on the "data types"{link: [perl 6 variable tablet] data types} of the values on both sides. Just look into that "large table"{link: [perl 6 lookup tablet] smartmatch} to check your specific case.
Smartmatching was originally invented to make "matching with regex"{link: [perl 6 regex tablet]Matching} semantically sane.
> ~~ !~
^^ Equality
> eqv eq == ===
> != !==
^^ Traversing Sequence
> ++ -- succ pred
"sequence generation"{link: Sequence Operator}
^^ Generic Comparison
> before after cmp
^^ Numerical Comparison
> < == > <=> <= >=
^^ String Comparison
> lt eq gt leg le ge
^^ joined comparison
> 3 < $a == $a < 7
is not the same as
> 3 < $a < 7
because latter is evaled at once and the first in 2 steps (left to right)
^^ Junctions
> | & ^ !
> any all one none
^^ Ranges
> .. ^
^^ logical selection
> && - and
> || - or
> // - err
> ^^ - xor
see also "numerical selection"{link: numerical selection}
^^ ternary
> ?? !!
^^ flipflop
> ff fff
^^ file test
"table"{link: [Perl 6 Lookup Tablet]Filetest Ops}
^^ yadda
> ...
> ???
> !!!
^ context forcing scalar ops
^^ bool context
> ? !
> ?& ?| ?^
^^ numeric context
> + - * ** / % %%
> +& +| +^ +< +>
> mod exp sqrt sin cos tan log log10
^^^ numerical selection
> min max minmax
^^ String context
> ~ x
> ~& ~| ~^ ~< ~>
^ Ops for arrays/lists
^^ List generation
The simplest way to create a list is by repeating some values:
> 'munch' xx 3 # results in 'munch', 'munch', 'munch'
> ('hallo', 'echo') xx 2 --> 'hallo', 'echo', 'hallo', 'echo'
In list context the range operator produces lists:
> @ 2 .. 7 --> 2,3,4,5,6,7
^^^ Sequence Operator
> ...
"traversing sequence"{link: Traversing Sequence}
^^ Zip
> Z
^^ Combinators
> X
^^ Hyperops
> << >>
^^ Reduce
> [ ]
^^ Triangle
> {{[\ ]}}
^^ Feed Ops
> <== ==>
> <<== ==>>
^ Assignment ops
^^ self assigning ops
^ precedence table
"is in Appendix B"{link: [Perl 6 Lookup Tablet]Table of precedence}
^ intentionally not existing ops
^ making own operators
----
"Overview"[Perl 6 Tablets] - _Chapter:_ "0:History"[Perl 6 History Tablet], "1:Design"[Perl 6 Language Design Tablet], "2:Basics"[Perl 6 Basics Tablet], "3:Var"[Perl 6 Variable Tablet], *"4:Op"[Perl 6 Operator Tablet]*, "5:IO"[Perl 6 IO Tablet], "6:{}"[Perl 6 Block Tablet], "7:Sub"[Perl 6 Subroutine Tablet], "8:OOP"[Perl 6 OOP Tablet], "9:Rx"[Perl 6 Regex Tablet], "10:Meta"[Perl 6 Meta Tablet]
"Intro"[Perl 6 Intro Tablet] - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], "C:Cook"[Perl 6 Cookbook Tablet], "D:Delta"[Perl 6 Delta Tablet], "E:Best of"[Best Of Perl 6 Tablet], "F:Links"[Perl 6 Links Tablet]
----
"Intro"[Perl 6 Intro Tablet] - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], "C:Cook"[Perl 6 Cookbook Tablet], "D:Delta"[Perl 6 Delta Tablet], "E:Best of"[Best Of Perl 6 Tablet], "F:Links"[Perl 6 Links Tablet]
----
{toc: }
_Perl folklore: Perl is an operator based language._
Perl 6 has a huge amount of operators, because they support 2 of the main design goals: they offer *dense* and *readable* code. _{{2 + 3}}_ is certainly shorter and easier to understand then _{{add(2,3)}}_, since "pictograms"{link: [perl 6 language design tablet] visual metaphor} can be picked up faster than words. (Fortran made his whole carrier on that). But because they are so many, they had to be sorted by a rule named "huffman coding"{link: [perl 6 language design tablet] huffman coding}, which was applied here more than in any other part of the syntax.
To understand an operator you have to know his *arity* (how many parameters he takes - usually one (!) or two (+) ).
The *"precedence"{link: [perl 6 lookup tablet]table of precedence}* tells which operator to prefer in case of conflict, when no braces are used (round braces are only used for grouping and managing precedence). It allows _{{2 + 3 * 5}}_ to return 17, not 25, which would upset your math teacher.
Behind that link is a table which also tells you also the *"associativity"{link: [perl 6 lookup tablet]Operator Associativity}* of every operator. This tells you after which rule to resolve precedence if one operator is used several times like in _{{2 * 3 * 7}}_.
^ Comparison
^^ Smartmatch
This is the most mighty (much more mighty than its backported Perl 5 twin) of all Perl 6 operators. It can be called the {{"compare-this-with-that-operator"}}. If the left side of that infix op matches somehow the content of the right side, it returns Bool::True, otherwise Bool::False. The negated form *!~* naturally works the other way around. The exact comparison operation depends on the "data types"{link: [perl 6 variable tablet] data types} of the values on both sides. Just look into that "large table"{link: [perl 6 lookup tablet] smartmatch} to check your specific case.
Smartmatching was originally invented to make "matching with regex"{link: [perl 6 regex tablet]Matching} semantically sane.
> ~~ !~
^^ Equality
> eqv eq == ===
> != !==
^^ Traversing Sequence
> ++ -- succ pred
"sequence generation"{link: Sequence Operator}
^^ Generic Comparison
> before after cmp
^^ Numerical Comparison
> < == > <=> <= >=
^^ String Comparison
> lt eq gt leg le ge
^^ joined comparison
> 3 < $a == $a < 7
is not the same as
> 3 < $a < 7
because latter is evaled at once and the first in 2 steps (left to right)
^^ Junctions
> | & ^ !
> any all one none
^^ Ranges
> .. ^
^^ logical selection
> && - and
> || - or
> // - err
> ^^ - xor
see also "numerical selection"{link: numerical selection}
^^ ternary
> ?? !!
^^ flipflop
> ff fff
^^ file test
"table"{link: [Perl 6 Lookup Tablet]Filetest Ops}
^^ yadda
> ...
> ???
> !!!
^ context forcing scalar ops
^^ bool context
> ? !
> ?& ?| ?^
^^ numeric context
> + - * ** / % %%
> +& +| +^ +< +>
> mod exp sqrt sin cos tan log log10
^^^ numerical selection
> min max minmax
^^ String context
> ~ x
> ~& ~| ~^ ~< ~>
^ Ops for arrays/lists
^^ List generation
The simplest way to create a list is by repeating some values:
> 'munch' xx 3 # results in 'munch', 'munch', 'munch'
> ('hallo', 'echo') xx 2 --> 'hallo', 'echo', 'hallo', 'echo'
In list context the range operator produces lists:
> @ 2 .. 7 --> 2,3,4,5,6,7
^^^ Sequence Operator
> ...
"traversing sequence"{link: Traversing Sequence}
^^ Zip
> Z
^^ Combinators
> X
^^ Hyperops
> << >>
^^ Reduce
> [ ]
^^ Triangle
> {{[\ ]}}
^^ Feed Ops
> <== ==>
> <<== ==>>
^ Assignment ops
^^ self assigning ops
^ precedence table
"is in Appendix B"{link: [Perl 6 Lookup Tablet]Table of precedence}
^ intentionally not existing ops
^ making own operators
----
"Overview"[Perl 6 Tablets] - _Chapter:_ "0:History"[Perl 6 History Tablet], "1:Design"[Perl 6 Language Design Tablet], "2:Basics"[Perl 6 Basics Tablet], "3:Var"[Perl 6 Variable Tablet], *"4:Op"[Perl 6 Operator Tablet]*, "5:IO"[Perl 6 IO Tablet], "6:{}"[Perl 6 Block Tablet], "7:Sub"[Perl 6 Subroutine Tablet], "8:OOP"[Perl 6 OOP Tablet], "9:Rx"[Perl 6 Regex Tablet], "10:Meta"[Perl 6 Meta Tablet]
"Intro"[Perl 6 Intro Tablet] - _Appendices:_ "A:Index"[Perl 6 Index Tablet], "B:Tables"[Perl 6 Lookup Tablet], "C:Cook"[Perl 6 Cookbook Tablet], "D:Delta"[Perl 6 Delta Tablet], "E:Best of"[Best Of Perl 6 Tablet], "F:Links"[Perl 6 Links Tablet]
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