What are you expecting to get with 1 .. /Q/?
The following code prints nothing as well: 
use Data::Dump;
Data::Dump::dd(1 .. /Q/);

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If your match-list is empty, nothing matches, and nothing is printed.
However, this does not explain why the last command *does* print something :)

Edit: Upon further reading, it looks like the range operator isn't parsed in scalar context, as the following does print something: perl -le " print for grep scalar 1 .. /Q/, @ARGV " a b c Q r s 

Output:
a
b
c
Q
r
s

[download]

In reply to Re: grep flip flop (range operator) by Neighbour
in thread grep flip flop (range operator) by Anonymous Monk

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