use YAPE::Regex::Explain; my $RE = qr/[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*@[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*|(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037]*(?:(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037]*)*<[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:@[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*(?:,[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*@[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*)*:[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)?(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*@[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*>)/; print YAPE::Regex::Explain->new($RE)->explain('regex'); __END__ (?x-ims: # group, but do not capture (disregarding # whitespace and comments) (case-sensitive) # (with ^ and $ matching normally) (with . not # matching \n): [\040\t]* # any character of: '\040', '\t' (tab) (0 or # more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more times # (matching the most amount possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', ')' # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) )* # end of grouping (?x: # group, but do not capture: (?x: # group, but do not capture: [^(\040)<>@,;:". # any character except: '(', '\040', \\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff]+ # '"', '.', '\\', '\[', '\]', '\000' to # '\037', '\x80' to '\xff' (1 or more # times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff] # '"', '.', '\\', '\[', '\]', '\000' # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR " # '"' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015"]* # '\xff', '\n' (newline), '\015', '"' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"]* # to '\xff', '\n' (newline), '\015', # '"' (0 or more times (matching the # most amount possible)) )* # end of grouping " # '"' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \. # '.' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff] # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR " # '"' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"]* # to '\xff', '\n' (newline), '\015', # '"' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"] # to '\xff', '\n' (newline), '\015', * # '"' (0 or more times (matching the # most amount possible)) )* # end of grouping " # '"' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping )* # end of grouping @ # '@' [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;:". # any character except: '(', '\040', \\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff]+ # '"', '.', '\\', '\[', '\]', '\000' to # '\037', '\x80' to '\xff' (1 or more # times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff] # '"', '.', '\\', '\[', '\]', '\000' # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): [^\\\x80- # any character except: '\\', '\x80' \xff\n\015\[\] # to '\xff', '\n' (newline), '\015', ] # '\[', '\]' | # OR \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \. # '.' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff] # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): [^\\\x80- # any character except: '\\', '\x80' \xff\n\015\[ # to '\xff', '\n' (newline), '\015', \]] # '\[', '\]' | # OR \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping )* # end of grouping | # OR (?x: # group, but do not capture: [^(\040)<>@,;:". # any character except: '(', '\040', \\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff]+ # '"', '.', '\\', '\[', '\]', '\000' to # '\037', '\x80' to '\xff' (1 or more # times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff] # '"', '.', '\\', '\[', '\]', '\000' # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR " # '"' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015"]* # '\xff', '\n' (newline), '\015', '"' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"]* # to '\xff', '\n' (newline), '\015', # '"' (0 or more times (matching the # most amount possible)) )* # end of grouping " # '"' ) # end of grouping [^()<>@,;:".\\\[\] # any character except: '(', ')', '<', \x80-\xff\000- # '>', '@', ',', ';', ':', '"', '.', '\\', \010\012-\037]* # '\[', '\]', '\x80' to '\xff', '\000' to # '\010', '\012' to '\037' (0 or more # times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' | # OR " # '"' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"]* # to '\xff', '\n' (newline), '\015', # '"' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"] # to '\xff', '\n' (newline), '\015', * # '"' (0 or more times (matching the # most amount possible)) )* # end of grouping " # '"' ) # end of grouping [^()<>@,;:".\\\[ # any character except: '(', ')', '<', \]\x80-\xff\000- # '>', '@', ',', ';', ':', '"', '.', \010\012-\037]* # '\\', '\[', '\]', '\x80' to '\xff', # '\000' to '\010', '\012' to '\037' (0 # or more times (matching the most # amount possible)) )* # end of grouping < # '<' [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture (optional # (matching the most amount possible)): @ # '@' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff] # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): [^\\\x80- # any character except: '\\', '\x80' \xff\n\015\[ # to '\xff', '\n' (newline), '\015', \]] # '\[', '\]' | # OR \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \. # '.' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' | # OR \( # '(' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most # amount possible)) (?! # look ahead to see if there is not: [^(\040)<> # any character except: '(', @,;:".\\\[ # '\040', ')', '<', '>', '@', ',', \]\000- # ';', ':', '"', '.', '\\', '\[', \037\x80- # '\]', '\000' to '\037', '\x80' \xff] # to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' \[\]] # (newline), '\015', '\[', '\]' | # OR \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' | # OR \( # '(' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): , # ',' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' | # OR \( # '(' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping @ # '@' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' | # OR \( # '(' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most # amount possible)) (?! # look ahead to see if there is not: [^(\040)<> # any character except: '(', @,;:".\\\[ # '\040', ')', '<', '>', '@', ',', \]\000- # ';', ':', '"', '.', '\\', '\[', \037\x80- # '\]', '\000' to '\037', '\x80' \xff] # to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' \[\]] # (newline), '\015', '\[', '\]' | # OR \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' | # OR \( # '(' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \. # '.' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' | # OR \( # '(' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x # any character except: 80- # '\x80' to '\xff' \xff # ] # [^\\ # any character except: \x80 # '\\', '\x80' to '\xff', - # '\n' (newline), '\015', \xff # '(', ')' (0 or more times \n\0 # (matching the most amount 15() # possible)) ]* # )* # end of grouping \) # ')' ) # end of grouping [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<> # any character except: '(', @,;:".\\\[ # '\040', ')', '<', '>', '@', ',', \]\000- # ';', ':', '"', '.', '\\', '\[', \037\x80- # '\]', '\000' to '\037', '\x80' \xff]+ # to '\xff' (1 or more times # (matching the most amount # possible)) (?! # look ahead to see if there is # not: [^(\040) # any character except: '(', <>@,;:". # '\040', ')', '<', '>', '@', \\\[\]\0 # ',', ';', ':', '"', '.', '\\', 00- # '\[', '\]', '\000' to '\037', \037\x80 # '\x80' to '\xff' -\xff] # ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '\[', '\]' 15\[\]] # | # OR \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): (?x: # group, but do not capture: \\ # '\' [^\x80 # any character except: '\x80' -\xff] # to '\xff' | # OR \( # '(' [^\\\x # any character except: '\\', 80- # '\x80' to '\xff', '\n' \xff\n # (newline), '\015', '(', ')' \015() # (0 or more times (matching ]* # the most amount possible)) (?x: # group, but do not capture (0 # or more times (matching the # most amount possible)): \\ # '\' [^\x # any character except: 80- # '\x80' to '\xff' \xff # ] # [^\\ # any character except: \x80 # '\\', '\x80' to '\xff', - # '\n' (newline), '\015', \xff # '(', ')' (0 or more times \n\0 # (matching the most amount 15() # possible)) ]* # )* # end of grouping \) # ')' ) # end of grouping [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' # (tab) (0 or more times (matching # the most amount possible)) )* # end of grouping )* # end of grouping )* # end of grouping : # ':' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping )? # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;:". # any character except: '(', '\040', \\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff]+ # '"', '.', '\\', '\[', '\]', '\000' to # '\037', '\x80' to '\xff' (1 or more # times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff] # '"', '.', '\\', '\[', '\]', '\000' # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR " # '"' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015"]* # '\xff', '\n' (newline), '\015', '"' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"]* # to '\xff', '\n' (newline), '\015', # '"' (0 or more times (matching the # most amount possible)) )* # end of grouping " # '"' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \. # '.' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff] # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR " # '"' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"]* # to '\xff', '\n' (newline), '\015', # '"' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015"] # to '\xff', '\n' (newline), '\015', * # '"' (0 or more times (matching the # most amount possible)) )* # end of grouping " # '"' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping )* # end of grouping @ # '@' [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;:". # any character except: '(', '\040', \\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff]+ # '"', '.', '\\', '\[', '\]', '\000' to # '\037', '\x80' to '\xff' (1 or more # times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80-\xff] # '"', '.', '\\', '\[', '\]', '\000' # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): [^\\\x80- # any character except: '\\', '\x80' \xff\n\015\[\] # to '\xff', '\n' (newline), '\015', ] # '\[', '\]' | # OR \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) (0 # or more times (matching the most amount # possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' to \xff\n\015()]* # '\xff', '\n' (newline), '\015', '(', # ')' (0 or more times (matching the # most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \. # '.' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping (?x: # group, but do not capture: [^(\040)<>@,;: # any character except: '(', '\040', ".\\\[\]\000- # ')', '<', '>', '@', ',', ';', ':', \037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff]+ # to '\037', '\x80' to '\xff' (1 or # more times (matching the most amount # possible)) (?! # look ahead to see if there is not: [^(\040)<>@, # any character except: '(', '\040', ;:".\\\[\]\0 # ')', '<', '>', '@', ',', ';', ':', 00-\037\x80- # '"', '.', '\\', '\[', '\]', '\000' \xff] # to '\037', '\x80' to '\xff' ) # end of look-ahead | # OR \[ # '[' (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): [^\\\x80- # any character except: '\\', '\x80' \xff\n\015\[ # to '\xff', '\n' (newline), '\015', \]] # '\[', '\]' | # OR \\ # '\' [^\x80-\xff] # any character except: '\x80' to # '\xff' )* # end of grouping \] # ']' ) # end of grouping [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): \( # '(' [^\\\x80- # any character except: '\\', '\x80' \xff\n\015()]* # to '\xff', '\n' (newline), '\015', # '(', ')' (0 or more times (matching # the most amount possible)) (?x: # group, but do not capture (0 or more # times (matching the most amount # possible)): (?x: # group, but do not capture: \\ # '\' [^\x80- # any character except: '\x80' to \xff] # '\xff' | # OR \( # '(' [^\\\x80- # any character except: '\\', \xff\n\015 # '\x80' to '\xff', '\n' ()]* # (newline), '\015', '(', ')' (0 # or more times (matching the most # amount possible)) (?x: # group, but do not capture (0 or # more times (matching the most # amount possible)): \\ # '\' [^\x80- # any character except: '\x80' \xff] # to '\xff' [^\\\x80 # any character except: '\\', - # '\x80' to '\xff', '\n' \xff\n\0 # (newline), '\015', '(', ')' (0 15()]* # or more times (matching the # most amount possible)) )* # end of grouping \) # ')' ) # end of grouping [^\\\x80- # any character except: '\\', '\x80' \xff\n\015() # to '\xff', '\n' (newline), '\015', ]* # '(', ')' (0 or more times # (matching the most amount # possible)) )* # end of grouping \) # ')' [\040\t]* # any character of: '\040', '\t' (tab) # (0 or more times (matching the most # amount possible)) )* # end of grouping )* # end of grouping > # '>' ) # end of grouping ) # end of grouping