Prefill an email_field with a template expression value

[fluca1978]

How can I prefill an email_field with the value that comes out from a Perl expression?
I've tried:

%= email_field 'email' => <%= $user && $user->is_logged_in ? $user->email : '' %>,  id => 'email', class => 'form-control'

and it partially works, since the email field is generated and filled, but it appears with all the other parts of the field configuration:

 <input name="email" type="email" value="foo@bar.com">,  id => 'email', class => 'form-control' %>

seems like a wrong escaping due to the expression ending tag.

[fluca1978]

I think I've solved by myself, but I would like to get a confirm or suggestion if this is not the best solution.
Since %= starts a Perl line evaluation, I do not need to embed <%= and I can insert the perl expression in the line:

%= email_field 'email' => ( $user && $user->is_logged_in ? $user->email : '' ),  id => 'email', class => 'form-control'

which produces:

<input class="form-control" id="email" name="email" type="email" value="foo@bar.com">

[ghandmann]

You are allowed to create local variables. So you could put the result of your expression into a variable and use that variable as value for the email_field:

% my $expression_result = "do something";
%= email_field 'email' => $expression_result;

[fluca1978]

Thanks @ghandmann, this is useful for more complex expressions!