You're just declaring a subroutine, there's no $app variable, which is what plackup is looking for.

Look at your example again:

my $app = sub {
    return [
        200,
        [ 'Content-Type' => 'text/plain' ],
        ['Hello World'],
    ];
};

[download]

Instead of declaring a subroutine, they are creating an anonymous sub and assigning it to the variable $app.

To make your code work, try the following:

my $app = \&app;

sub app {
     my $env = shift;
     return [
         '200',
         [ 'Content-Type' => 'text/plain' ],
         [ "Hello World" ]
     ];
 }

[download]

This version assigns a reference to the subroutine app to the variable $app, which is the code reference plackup is looking for.

In reply to Re: plackup problem by three18ti
in thread plackup problem by Perler#2

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