Vectorized over str and pattern.
stri_trim is a convenience wrapper over stri_trim_left
and stri_trim_right.
Contrary to many other string processing libraries,
our trimming functions are universal. A character class,
given by pattern, may be adjusted to suit your needs
(yet, most often you stick to the default value).
For replacing pattern matches with
arbitrary replacement string, see stri_replace.
Trimming can also be used where you would normally rely on
regular expressions. For instance, you may get
"23.5" out of "total of 23.5 bitcoins".
For trimming white-spaces, please note the difference
between Unicode binary property `\p{Wspace}` (more universal)
and general character category `\p{Z}`,
see stringi-search-charclass.