my Str $data = slurp $file_name;
my $fh = IO::String.new($data);
my $csv = Text::CSV.new(';', '"');	
my @column = $csv.getline_all($fh).map( *[$target_col] );

##</code><code>##

> raku clean_class.raku PPP_DSP_2002-2021.csv
Flattened array has 150000 elements, but argument lists are limited to 65535
  in method print at C:\workbench\budget\lib\IO\String.pm6 (IO::String) line 40
  in method new at C:\workbench\budget\lib\IO\String.pm6 (IO::String) line 26
  in method new at C:\workbench\budget\lib\IO\String.pm6 (IO::String) line 13
  in sub MAIN at clean_class.raku line 77
  in block  at 'SETTING::'src/core.c/Main.pm6 line 421
  in sub RUN-MAIN at 'SETTING::'src/core.c/Main.pm6 line 416
  in block <unit> at clean_class.raku line 15

##</code><code>##

        @!content.push: |@x;

##</code><code>##

        @!content.push: $_ for @x;