$file.IO.lines( :nl-in(…), :chomp, … )
is actually short for
$file.IO.open( :nl-in(…), :chomp ).lines( … )
On Sun, Aug 30, 2020 at 10:43 AM yary <not....@gmail.com> wrote:
> You were close!
>
> First, you were looking at the docs for Path's "lines", but you are using
> a string "lines" and those docs say
>
> multi method lines(Str:D: $limit, :$chomp = True)
> multi method lines(Str:D: :$chomp = True)
>
> Files get "nl-in" due to the special case of text files having various
> line endings to tweak.
>
> Strings already have "split" and "comb" for all the flexibility one may
> need there, and what you're playing with is more naturally
> dd $_ for $x.split("\t"); # "a","b", ... removes \t
> dd $_ for $x.split(/<?after \t>/); "a\t","b\t", ....
>
> Now back to the Path lines, which DOES let you specify line endings
>
> method lines(IO::Path:D: :$chomp = True, :$enc = 'utf8', :$nl-in = ["\x0A"
> , "\r\n"], |c --> Seq:D)
>
> $ cat line0-10.txt
> Line 0
> Line 1
> Line 2
> ...
>
> let's pretend that the letter "i" is a line ending.
> named arguments can be conveniently written colon pairs :-)
>
> my $nl-in="i"; dd $_ for 'line0-10.txt'.IO.lines(:$nl-in)[0..3];
> "L"
> "ne 0\nL"
> "ne 1\nL"
> "ne 2\nL"
>
> How about splitting on either "i" or "\n", and not chomping
>
> my $nl-in=("i","\n"); dd $_ for 'line0-10.txt'.IO.lines(:$nl-in,
> :!chomp)[0..3];
> "Li"
> "ne 0\n"
> "Li"
> "ne 1\n"
>
> To put in line endings without having a variable of the same name as the
> naed arg, use the full form of the colon pair
> dd $_ for 'line0-10.txt'.IO.lines(:nl-in["i","\n"], :!chomp)[0..3];
> "Li"
> "ne 0\n"
> "Li"
> "ne 1\n"
>
>
>
> -y
>
>
> On Sun, Aug 30, 2020 at 2:58 AM ToddAndMargo via perl6-users <
> perl6-users@perl.org> wrote:
>
>> Hi All,
>>
>> https://docs.raku.org/type/IO::Path#method_lines
>>
>> method lines(IO::Path:D: :$chomp = True, :$enc = 'utf8', :$nl-in =
>> ["\x0A", "\r\n"], |c --> Seq:D)
>>
>> How do I change what lines sees as a new line. Is it
>> :$nl-in? A tab in this case.
>>
>> Some of my missteps:
>>
>> $ p6 'my $x="a\tb\tc\td\t"; dd $x; for $x.lines(:!chomp, "\t") {dd $_};'
>> Str $x = "a\tb\tc\td\t"
>>
>>
>> $ p6 'my $x="a\tb\tc\td\t"; dd $x; for $x.lines(:!chomp, :$nl-in =
>> ["\x0A", "\r\n"]) {dd $_};'
>> ===SORRY!=== Error while compiling -e
>> Variable '$nl-in' is not declared
>> at -e:1
>> ------> tc\td\t"; dd $x; for $x.lines(:!chomp, :⏏$nl-in = ["\x0A",
>> "\r\n"]) {dd $_};
>>
>> $ p6 'my $x="a\tb\tc\td\t"; dd $x; for $x.lines(:!chomp, :nl-in =
>> ["\x0A", "\r\n"]) {dd $_};'
>> Str $x = "a\tb\tc\td\t"
>> Cannot modify an immutable Pair (nl-in => True)
>> in block <unit> at -e line 1
>>
>>
>> Many thanks,
>> -T
>>
>
