Perl6:如何动态加载类模块？

Question

如何动态加载OO样式的模块？

#!/usr/bin/env perl6
use v6;

my $r = prompt ':';

if $r {
    require Text::CSV;          # Error:
    my $csv = Text::CSV.new;    # Could not find symbol '&CSV'
} else {
    require File::Temp <&tempfile>;
    my ( $filename , $filehandle ) = tempfile; # this works
}

Answer 1

正如perl6 DOCO解释在这里,你可以动态加载模块,但是,

要导入符号,必须在编译时定义它们.

因此,else由于显式的导入请求,该子句中的代码可以工作<&tempfile>.

让if我能看到的子句中的代码最接近的是(这主要取自早期的doco引用):

use v6.c ;

sub load-a-module($name) {
   require ::($name) ;
   my $instance = ::($name).new() ;
   return $instance ;
}

my $module = "Text::CSV" ;
my $csv = load-a-module $module ;
say $csv.WHAT ;
# say $csv.^methods ;   # if you really want to be convinced

# outputs: (CSV)