I'm wondering if there is a way to import a sub from another package as a lexical sub without using non-core modules.

The motivation is that I like to ship CPAN modules with the fewest dependencies possible for the sake of minimalism. A common desire when authoring the module is to use functions from other packages, but not litter my method namespace with those functions. The "best practice" way to do that is: 

use Scalar::Util 'looks_like_number';
use namespace::clean;


... looks_like_number($x) ...

[download]
but namespace::clean is not a core module. The most minimal of all options is to just reference the function by its full name: 
use Scalar::Util ();


... Scalar::Util::looks_like_number($x) ...

[download]
but that is tedious and makes me unhappy while writing the code.

I have the option of lexical subs: 

use v5.20;
use experimental 'lexical_subs';
use Scalar::Util ();
my sub looks_like_number { &Scalar::Util::looks_like_number }

... looks_like_number($x) ...

[download]
but I'm introducing a tiny bit of runtime inefficiency for the sake of more pleasant authoring.

What I really want is: 

use v5.20;
use experimental 'lexical_subs';
use Scalar::Util ();
my sub looks_like_number = \&Scalar::Util::looks_like_number;

... looks_like_number($x) ...

[download]
but this gives me "Illegal declaration of subroutine looks_like_number".

Is there any way in pure-perl with only core modules to achieve a lexical sub which *is* the same coderef as the fully qualified global name?

In reply to Pure perl lexical sub import by NERDVANA

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