The example that BorgCopyeditor supplies with his question brings up an interesting point. Why does this work:      if($query=~$term) {...} Or, to offer a very plain example, why does this work: 
     if ( 'abc' =~ 'bc' ) {
        print "yes\n";
     }

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The rule I learned was (quoting from perlop): "If "/" is the delimiter then the initial m is optional."

Fair enough. The implication is: 

     if ( 'abc' =~ m/bc/ ) {  # good
     if ( 'abc' =~  /bc/ ) {  # good
     if ( 'abc' =~ m%bc% ) {  # good (for any non-alphanum)
  but:
     if ( 'abc' =~  'bc' ) {  # BAD! (or so we assume)

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But it is not so. As I said above, both of the examples at the top of this response work. Why?

What I cannot find in the on-line docs (update: see danger's response below) but I know from experimentation and the words of Camel 3, page 144, is that, even without the 'm' or the '/', the righthand side of =~ "still counts as a m// matching operation, but there'll be no place to put any trailing modifiers, and you'll have to handle your own quoting."

So... 

     if ( 'abc' =~ 'bc' ) {       # works
     if ( 'abc' =~ $pattern ) {   # works
     if ( 'abc' =~ "$pattern" ) { # works
     if ( 'abc' =~ bc ) {         # works!!
     if ( 'abc' =~ 'bc'g ) {      # Error: bareword 'g'

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The present writer is not responsible for any sideways looks any of these may earn you from your peers.

------------------------------------------------------------
"Perl is a mess and that's good because the
problem space is also a mess." - Larry Wall

In reply to Regex without 'm' or '/' by dvergin
in thread Am I on the pipe, or what? by BorgCopyeditor

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