Tell me more about modifiers
The backslash not only turns meta-characters into literal characters, it is also used to give otherwise literal characters special meaning. In the Perl-compatible regular expressions supported by Observer, this includes modifiers or controls that affect the way the entire expression is interpreted. For example, regular expressions are case-sensitive unless you use the /i modifier:
/network instruments/i
Would match:
Network Instruments and NETWORK INSTRUMENTS and Network instruments
Table 14 lists the modifiers supported by Observer’s regular expression filters. For more comprehensive definitions of all the meta-characters supported by Perl-compatible regular expressions, see
Table 14. Modifiers
Make the search case insensitive.
Interpret the period (.) meta-character to include newlines.
By default, the string is treated as one big line of characters. ˆ and $ (two other meta-characters) match at the beginning and ending of the string. When \m is set, ˆ and $ match immediately following or immediately before any newline in the buffer, as well as the very start and very end of the buffer.
Whitespace data characters in the pattern are ignored unless escaped or inside a character class. This is useful for making long regular expressions more readable.
The pattern must match only at the start of the buffer (same as ˆ)
Set $ to match only after the subject string. Without E, $ also matches immediately before the final character if it is a newline (but not before any other newlines).
Inverts the greediness of the quantifiers so that they are not greedy by default, but become greedy if followed by a question mark (?). Greediness refers to how many characters it will consider when trying to match strings of variable length.