diff options
| -rw-r--r-- | perl6.html.markdown | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/perl6.html.markdown b/perl6.html.markdown index 4ab90914..fe5b197c 100644 --- a/perl6.html.markdown +++ b/perl6.html.markdown @@ -488,6 +488,7 @@ sub truthy-array(@array) { # (it'll stop at the furthest operator in the current expression) my @arrayplus3 = map(*+3, @array); # `*+3` is the same as `{ $_ + 3 }` my @arrayplus3 = map(*+*+3, @array); # Same as `-> $a, $b { $a + $b + 3 }` + # also `sub ($a, $b) { $a + $b + 3 }` say (*/2)(4); #=> 2 # Immediatly execute the function Whatever created. say ((*+3)/5)(5); #=> 1.6 @@ -496,7 +497,8 @@ say ((*+3)/5)(5); #=> 1.6 # But if you need to have more than one argument (`$_`) # in a block (without wanting to resort to `-> {}`), # you can also use the implicit argument syntax, `$^` : -map({ $^a + $^b + 3 }, @array); # same as the above +map({ $^a + $^b + 3 }, @array); # equivalent to following: +map(sub ($a, $b) { $a + $b + 3 }, @array); # (here with `sub`) # Note : those are sorted lexicographically. # `{ $^b / $^a }` is like `-> $a, $b { $b / $a }` @@ -1072,6 +1074,11 @@ my @list = 1, 3, 9 ... { $_ > 30 }; # (equivalent to the above) my @fib = 1, 1, *+* ... *; # lazy infinite list of prime numbers, # computed using a closure! my @fib = 1, 1, -> $a, $b { $a + $b } ... *; # (equivalent to the above) +my @fib = 1, 1, { $^a + $^b } ... *; #(... also equivalent to the above) +# $a and $b will always take the previous values, meaning here +# they'll start with $a = 1 and $b = 1 (values we set by hand). +# then $a = 1 and $b = 2 (result from previous $a+$b), and so on. + say @fib[^10]; #=> 1 1 2 3 5 8 13 21 34 55 # (using a range as the index) # Note : as for ranges, once reified, elements aren't re-calculated. |