use v5.10;  
use warnings;

foreach ( 'a', 'z', 5..11 ) {
    when( /a/ ) { say "$_ : ", 'Matched an a' }  
    when( [ 2..5 ] ) { say "$_ : Matched 2 through 5" }  #line 7
    when( [ 6..10 ] ) { say "$_ : Matched 6 through 10" }  
    default     { say "$_ : Matched nothing" }  
}

##</code><code>##

a : Matched an a
Argument "z" isn't numeric in smart match at C:\b\perlmonks\switch.pl line 7.
z : Matched nothing
5 : Matched 2 through 5
6 : Matched 6 through 10
7 : Matched 6 through 10
8 : Matched 6 through 10
9 : Matched 6 through 10
10 : Matched 6 through 10
11 : Matched nothing