##
m/^(?! .*? $a ) .*? $end/sx
##
##
$_ = '...
... foo';
if (m{^(?! .*? foo ) .*? }sx){
print "Match\n";
}
# no match
####
m/^ (?: . (?! $a ) )* $end /sx
##
##
$_ = 'foo...
... ';
if (m{^(?: . (?! .*? foo ))* }sx){
print "Match\n";
}
# match
####
m/^ (?: (?! $a ) . )* $end /sx