Re: `lines.contains( / \h / )` returning True for input strings not containing horizonal whitespace

lines.contains...  is really short for:  lines.Str.contains...

Do you then understand what's going on?

> On 28 Jan 2023, at 21:41, William Michels via perl6-users <[email protected]> wrote:
> 
> Some more examples:
> 
> ~$ raku -e 'put "1\n2\n3";' | raku -e 'lines.contains(/ \h /).put;'
> True
> ~$ raku -e 'put "1\02\03";' | raku -e 'lines.contains(/ \h /).put;'
> False
> ~$ raku -e 'put "1\02\03";' | raku -e 'lines.contains(/ 12 /).put;'
> False
> ~$ raku -e 'put "1\02\03";' | raku -e 'lines.contains(/ "1 2" /).put;'
> False
> ~$
> 
> So what I don't understand is how`.contains` coerces  `\0` null-separated strings to a `Str` without whitespace, but coerces  `\n` newline-separated strings to a `Str` with whitespace. Furthermore, it seems that `\0` null-separated strings are correctly processed so that concatenation artifacts such as "12" string or "1 2" string are not produced. 
> 
> And if  `.contains` can coerce `\0` null-separated strings to a Str without whitespace, can't it do the same for `\n` newline separated strings? What am I missing?
> 
> Best Regards, Bill.
> 
> PS. Typo:  of course, that title should read 'horizontal', not 'horizonal'.
> 
> On Thu, Jan 26, 2023 at 3:40 PM William Michels <[email protected]> wrote:
> Thanks Sean.
> 
> Made some progress. I like this result better:
> 
> ~$ raku -e 'put "1\n2\n3";' | raku -e 'lines.map(*.contains(/ \h /)).put;'
> False False False
> 
> Thx, Bill.
> 
> On Thu, Jan 26, 2023 at 12:12 PM Sean McAfee <[email protected]> wrote:
> On Thu, Jan 26, 2023 at 12:05 PM William Michels via perl6-users <[email protected]> wrote:
> ~$ raku -e 'put "1\n2\n3";' | raku -e 'put lines.contains(/ \h /) ?? True !! False;'
> True
> 
> lines() returns a Seq.  The contains method for a Seq coerces its argument to a Str and calls contains on that Str.  And:
> 
> $ raku -e 'put "1\n2\n3"' | raku -e 'put lines.Str'
> 1 2 3
> 
> There's your horizontal whitespace.
>