> On 30 Apr 2018, at 15:12, ToddAndMargo <toddandma...@zoho.com> wrote:
>
> On 04/30/2018 05:44 AM, Elizabeth Mattijsen wrote:
>>> On 30 Apr 2018, at 12:43, ToddAndMargo <toddandma...@zoho.com> wrote:
>>>
>>>
>>>> Am 30.04.2018 um 08:47 schrieb ToddAndMargo:
>>>>> Hi All,
>>>>>
>>>>> I know it would only take me 25 seconds to write one,
>>>>> but do we have an odd and even function build in?
>>>>>
>>>>>
>>>>> Many thanks,
>>>>> -T
>>>>>
>>>>> $ perl6 -e 'my $x=3; say $x.odd;'
>>>>> No such method 'odd' for invocant of type 'Int'. Did you mean 'ord'?
>>>>> in block <unit> at -e line 1
>>>>>
>>>>> $ perl6 -e 'my $x=3; say $x.even;'
>>>>> No such method 'even' for invocant of type 'Int'
>>>>> in block <unit> at -e line 1
>>>
>>> On 04/30/2018 02:05 AM, Martin Barth wrote:
>>>> Are you aware of the %% operator?
>>>>
>>>> $var %% 2 checks wether it is dividable by 2.
>>>>
>>>>
>>>
>>> No I was not. Thank you!
>>>
>>> I was just going to do a
>>>
>>> sub odd( $Num ) { return $Num % 2; }
>>> sub even( $Num ) { return not $Num.odd; }
>> If you create this sub to do value checking, then maybe this approach is
>> better for you:
>> subset EvenInt of Int where * %% 2; # all the even Ints
>> subset OddInt of Int where * !%% 2; # all the odd Ints
>> # works
>> my EvenInt $x = 42;
>> # dies with: Type check failed in assignment to $y; expected EvenInt but
>> got Int (42)
>> my OddInt $y = 42;
>> Liz
>
> I don't get it. Why would I want to do this? I only want to know if
> an integer is odd or even. What am I missing?
>
> For example, I just coded this:
>
> sub odd( $Num ) { return $Num % 2; }
>
> for split( "\n", $ClipStr ).kv -> $LineNum, $Line {
> if odd $LineNum
> { $PartsStr ~= '<font color="#006600">'; } # Green
> else { $PartsStr ~= '<font color="#663366">'; } # Purple
> ...
> }
>
> It allows me to alternate the color for odd and even lines.
>
> Please remember that I have about 1/100 of your skill when you
> explain things to me. (For instance, I have no clue what
> `subset` is or how to use it.)
A subset creates a new Type (like Int) from a base type (such as Int) and
narrows down the condition that is acceptable for it.
https://docs.perl6.org/language/typesystem#index-entry-subset-subset
