Invalid regular expression:Lone quantifier brackets

Question

I have a html phone pattern that will accept these formats :

+61 x xxxx xxxx,
+61xxxxxxxxx,
0x xxxx xxxx,
0xxxxxxxxx,
xxxx xxxx,
xxxxxxxx,
+xx xxx xxx xxx,
+xxxxxxxxxxx,
0xxx xxx xxx,
0xxxxxxxxx

It was working few months ago, now suddenly my phone fields are not validating . I'm having this error:

Pattern attribute value ^(?:0|\(?\+61\)?\s?|0061\s?)[1-79](?:[\.\-\s]?\d\d){4}|(\d{4}[\s]\d{4})|(\d{8})|(\d{4}[\s]\d{3}[\s]\d{3})|(\+61\[\s]\d{3}[\s]\d{3}[\s]\d{3})|(\+61\s\d{3}\s\d{3}\s\d{3})$ is not a valid regular expression: Uncaught SyntaxError: Invalid regular expression: /^(?:0|\(?\+61\)?\s?|0061\s?)[1-79](?:[\.\-\s]?\d\d){4}|(\d{4}[\s]\d{4})|(\d{8})|(\d{4}[\s]\d{3}[\s]\d{3})|(\+61\[\s]\d{3}[\s]\d{3}[\s]\d{3})|(\+61\s\d{3}\s\d{3}\s\d{3})$/: Lone quantifier brackets 

Answer 1

So far, no one cared to show where in your pattern the error is.

…|(\+61\[\s]\d{3}[\s]\d{3}[\s]\d{3})|(\+61\s\d{3}\s\d{3}\s\d{3})$
       ^

There by mistake you inserted a backslash, escaping the opening bracket, so making it an ordinary character and leaving the closing bracket Lone. (Sadly the error message is somewhat misleading, since those brackets are of course not quantifier brackets.)