pattern
is empty,
then all functions in NA
in result
and generate a warning.
On a syntax error, a quite informative failure message is shown.If you would like to search for a fixed pattern, refer to stringi-search-coll or stringi-search-fixed. This allows to do a locale-aware text lookup, or a very fast exact-byte search, respectively.
stri_*_regex
functions in stri_opts_regex
function for more details.
Regular expression patterns in java.util.regex
.
J.E.F. Friedl, Mastering Regular Expressions, O'Reilly, 2002
Unicode Regular Expressions -- Unicode Technical Standard #18,
Unicode Regular Expressions -- Regex tutorial,
stri_opts_regex
;
stringi-search
Other stringi_general_topics: stringi-arguments
;
stringi-encoding
;
stringi-locale
;
stringi-search-boundaries
;
stringi-search-charclass
;
stringi-search-coll
;
stringi-search-fixed
;
stringi-search
; stringi
,
stringi-package