if($query=~$term) {...}

##</code><code>##

     if ( 'abc' =~ 'bc' ) {
        print "yes\n";
     }

##</code><code>##

     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)

##</code><code>##

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