Do regular expressions from the re module support word boundaries (\b)?

Question

While trying to learn a little more about regular expressions, a tutorial suggested that you can use the \\b to match a word boundary. However, the following sn

Answer 1

Just to explicitly explain why re.search("\btwo\b", x) doesn't work, it's because \b in a Python string is shorthand for a backspace character.

print("foo\bbar")
fobar

So the pattern "\btwo\b" is looking for a backspace, followed by two, followed by another backspace, which the string you're searching in (x = 'one two three') doesn't have.

To allow re.search (or compile) to interpret the sequence \b as a word boundary, either escape the backslashes ("\\btwo\\b") or use a raw string to create your pattern (r"\btwo\b").