XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition (646 page)

The metacharacter
.
in a regex matches any single character except a newline character (x0A), except when the
s
(dot-all) flag is set, in which case it matches any character including a newline.

The metacharacters
∧
and
$
match the beginning and end of the input string, respectively, except when the
m
(multiline) flag is set, in which case they match the beginning and end of each line. The beginning of a line is either the start of the entire string or the position immediately after a newline (x0A) character; the end of a line is either the end of the entire string or the position immediately before a newline character. So (with multiline mode off) the regex
∧
The
matches a string that begins with the characters
The
, while the regex
\.xml$
matches a string that ends with the characters
.xml