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switcheroo operators

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Nami-Doc 2014-07-10 22:23:56 +02:00
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@ -130,25 +130,12 @@ if long-computation() -> $result {
## The categories are :
### - "prefix" : before (like `!` in `!True`).
### "postfix" : after (like `++` in `$a++`).
### "infix" : in between (like `*` in `4 * 3`).
### "circumfix" : around (like `[`-`]` in `[1, 2]`).
### "post-circumfix" : around, after another term (like `{`-`}` in `%hash{'key'}`)
### - "postfix" : after (like `++` in `$a++`).
### - "infix" : in between (like `*` in `4 * 3`).
### - "circumfix" : around (like `[`-`]` in `[1, 2]`).
### - "post-circumfix" : around, after another term (like `{`-`}` in `%hash{'key'}`)
## The precedence list can be found here : http://perlcabal.org/syn/S03.html#Operator_precedence
## But first, we need a little explanation about associativity :
### Binary operators:
$a ! $b ! $c; # with a left-associative `!`, this is `($a ! $b) ! $c`
$a ! $b ! $c; # with a right-associative `!`, this is `$a ! ($b ! $c)`
$a ! $b ! $c; # with a non-associative `!`, this is illegal
$a ! $b ! $c; # with a chain-associative `!`, this is `($a ! $b) and ($b ! $c)`
$a ! $b ! $c; # with a list-associative `!`, this is `infix:<>`
### Unary operators:
!$a! # with left-associative `!`, this is `(!$a)!`
!$a! # with right-associative `!`, this is `!($a!)`
!$a! # with non-associative `!`, this is illegal
## The associativity and precedence list are explained below.
## Alright, you're set to go !
@ -180,6 +167,40 @@ $arg ~~ &bool-returning-function; # true if the function, passed `$arg` as an ar
### Their string equivalent are also avaiable : `lt`, `le`, `gt`, `ge`.
3 > 4;
## * Range constructors
3 .. 7; # 3 to 7, both included
### `^` on either side them exclusive on that side :
3 ^..^ 7; # 3 to 7, not included (basically `4 .. 6`)
# * And, Or
3 && 4; # True. Calls `.Bool` on `3`
0 || False; # False. Calls `.Bool` on `0`
## Short-circuit (and tight)
$a && $b && $c; # returns the first argument that evaluates to False, or the last argument
$a || $b;
# More operators thingies !
## Everybody loves operators ! Let's get more of them
## The precedence list can be found here : http://perlcabal.org/syn/S03.html#Operator_precedence
## But first, we need a little explanation about associativity :
### Binary operators:
$a ! $b ! $c; # with a left-associative `!`, this is `($a ! $b) ! $c`
$a ! $b ! $c; # with a right-associative `!`, this is `$a ! ($b ! $c)`
$a ! $b ! $c; # with a non-associative `!`, this is illegal
$a ! $b ! $c; # with a chain-associative `!`, this is `($a ! $b) and ($b ! $c)`
$a ! $b ! $c; # with a list-associative `!`, this is `infix:<>`
### Unary operators:
!$a! # with left-associative `!`, this is `(!$a)!`
!$a! # with right-associative `!`, this is `!($a!)`
!$a! # with non-associative `!`, this is illegal
## And to end the list of operators ...
## * Sort comparison
### They return one value of the `Order` enum : `Less`, `Same` and `More` (which numerify to -1, 0 or +1).
1 <=> 4; # sort comparison for numerics
@ -190,14 +211,4 @@ $obj eqv $obj2; # sort comparison using eqv semantics
3 before 4; # True
'b' after 'a'; # True
## * Range constructors
3 .. 7; # 3 to 7, both included
### `^` on either side them exclusive on that side :
3 ^..^ 7; # 3 to 7, not included (basically `4 .. 6`)
# * And, Or
## Short-circuit (and tight)
$a && $b && $c; # returns the first argument that evaluates to False, or the last argument
$a || $b;
```