et-regular-expression-search-modifiers.md

One or more single-character flags that modify how the regular expression pattern is matched to string-expression:

  • b: Treat strings as binary octets, rather than UTF-8 characters.

  • c (default): Force the match to be case sensitive.

  • i: Force the match to be case insensitive.

  • m: Treat the string to match as multiple lines. Using this modifier, the start of line (^) and end of line ($) regular expression operators match line breaks (\n) within the string. Without the m modifier, the start and end of line operators match only the start and end of the string.

  • n: Match the regular expression operator (.) to a newline (\n). By default, the . operator matches any character except a newline.

  • x: Add comments to regular expressions. The x modifier causes the function to ignore all un-escaped space characters and comments in the regular expression. Comments start with hash (#) and end with a newline (\n). All spaces in the regular expression to be matched in strings must be escaped with a backslash (\).