java - Is escaped hyphen equal to unescaped hyphen?

Question

using java regular expression , and I found the following example

Print\-Services

I am wondering why \-, does it escape the -?

Answer 1

You don't need to escape a '-' in a regex. It is only a meta-character inside a [...] character class specification.

If that was a Java String literal, then the first '' would escape the 2nd '' and that would give - in the regex ... which is nonsense¹.

If that was NOT a String literal, then the first '' is escaping the 2nd '' in the regex. That is NOT nonsense. It means match a backslash character.

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^{1 - It is, however, legal nonsense. The javadoc says: "A backslash may be used prior to a non-alphabetic character regardless of whether that character is part of an unescaped construct." The redundant backslash would be ignored.}