P6WREGEXMODIFIER: Regex Modifier.
This type defines how to modify (or adjust) the matching process. The elements of this type form a bit mask when combined. These are global to a match and can be over ridden by Perl Cloisters (i.e., '(?ism: )' ).
* P6MOD_INSENSITIVE - same as Perl's "/i" modifier, case-insensitive matching
* supported in both Perl and Egrep regex flavors
* use in match, search, or replace
*
* P6MOD_MULTILINE - same as Perl's "/m" modifer, allows '^' and '$' meta characters can match next to
* newlines within the input string instead of only matching the ends of a string
* supported in both Perl and Egrep regex flavors
* use in match, search, or replace
*
* P6MOD_NEWLINE - same as Perl's "/s" modifier, allows '.' meta charcter will match newlines
* supported in both Perl and Egrep regex flavors
* use in match, search, or replace
*
* P6MOD_FASTGREEDY - use greedy matching (includes greedy alternation) by use of fast DFA like matching,
* supported in both Perl and Egrep regex flavors
* use in match, search, or replace
*
* P6MOD_GLOBAL - same as Perl's "/g" modifier, replace all instances of matched string,
* supported in both Perl and Egrep regex flavors
* use only in replace
*
* P6MOD_FULLLOOKBEHIND - allows Perl's lookbehind meta character sequences, (?<= & (?<! , to search the entire target
* string already seen. Standard lookbehind only looks at the immediate characters just behind
* the current match point, supported in Perl only
* use in match, search, replace
*
* P6MOD_SKIPWHITESPACE - similar to Perl's "/x" modifier, ignore whitespace in the regex except in character classes,
* supported in both Perl and Egrep
* use only in compile
*
