use WWW::Mechanize::Chrome;

my $mech = WWW::Mechanize::Chrome->new(   
        headless => 1  
);
my $console = $mech->add_listener('Runtime.consoleAPICalled', sub { 
  warn join ", ",
      map { $_->{value} // $_->{description} }
      @{ $_[0]->{params}->{args} };
});

$mech->get('https://google.com');

# SyntaxError: Illegal return statement at xx line 17.
$mech->eval_in_page('if(1){console.log("aaa"); return;} console.log("b
+bb");');

# ReferenceError: exit is not defined
$mech->eval_in_page('if(1){console.log("aaa"); exit;} console.log("bbb
+");');

# Works but is there anything simpler???
$mech->eval_in_page('function xxx(){if(1){console.log("aaa"); return;}
+ console.log("bbb");} xxx();');

[download]

So the question is: how can I have some flow control in eval'ed JS which terminates and returns back to perl? On an error condition say.

The context is: I am trying to get a screenshot of browser's contents using WWW::Mechanize::Chrome. But first I am removing a few HTML elements which obstruct the view, like footers and banners, etc. So, in removing the elements using JS I am sometimes in need to say "element not found" and return back to perl. Of course I can wrap everything in lots and lots of if-then-else but JS has already a lot of curly brackets as it is...

I had the idea of wrapping everything into a single JS function and then return will work just fine. Is there a better, simpler solution?

Many Thanks, bliako

In reply to WWW::Mechanize::Chrome : how to terminate JS code in eval() and return? (OT JS) by bliako

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