Common: http://www.perldoc.com/perl5.6/pod/perlop.html

~
ones complement
+
Add two numbers together (if you are lucky). Other than that, it has no effect whatsoever, even on strings. ( use .= to concatonate ). However, It is useful syntactically for separating a function name from a parenthesized expression that would otherwise be interpreted as the complete list of function arguments.
print ($foo & 255) + 1, "hello";

prints the lower 8 bits of $foo and does not add 1 or print "hello" because the paran around $foo & 255 make print stop working at the ")" The 1 and "hello" are evaluated as seperate statements.

print +($foo & 255) + 1, "hello";

prints "9hello"
See http://www.perldoc.com/perl5.6/pod/perlop.html#Terms_and_List_Operators_Leftwa

\
Creates a reference to whatever follows it. See the perlref manpage. Do not confuse this behavior with the behavior of backslash within a string, although both forms do convey the notion of protecting the next thing from interpretation. See
http://www.perldoc.com/perl5.6/pod/perlref.html

See also:

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