Does anyone else think that adding /e to qr// would be a good idea? I recently found myself doing something like this: 
   my @days    = qw( Sun Mon Tue Wed Thu Fri Sat );
   my $days_re = qr/join '|', @days/e;

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And was quite surprised that it didn't just work. There are obvious workarounds, but they feel awkward: 
   my $days_re = do { my $tmp = join '|', @days; qr/$tmp/ };

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(Yes, in this particular case, I could abuse $"... but that still takes a do BLOCK and a local.)

Update

  1. Yes, I know that this is not how the language works right now. What I was trying to ask is whether others thought this might be an interesting or useful or non-damaging feature.
  2. Note that I am only suggesting /e apply to the regex guts in qr//. Not in m//, not in s///.
  3. I tried to demonstrate in my example that I would like the /e to apply exactly once, at the time the qr// is evaluated. I understand that this is not how the other qr// modes work (as they are applied at time of use). This is exactly the sort of wart that I was hoping people would point out, and it is appreciated.
  4. I also discussed this on at least one PM list, so I might be confused about what I clarified there vs. what I clarified here. :) Apologies!

So far, people (including myself! :) have demonstrated that this is not a necessary feature. The opinion seems mostly against whether this would be a desirable feature.

It is just a pattern that I've found myself using quite often lately. My preference for a one-line approach is that I like the most important things to be closer to the left side: what I really want to know is that I'm compiling a regex object. Whether I'm building it via a perl expression or by string expansion or by literal is less important to me.

In reply to qr// with /e? by tkil

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