Surname regular expression

Question

I'm trying to create a good regular expression for people's Surname.

It should be valid if a Surname is:

abcd

abcd'efg

abcd-efg

abcd, .efg

etc...

I also need to test if symbols do not repeat... so for example:

abcd''efg

abcd-',

Are invalid but the one:

abcd, .efg

Can be valid.

At the moment I just created this:

^[a-z .',-_]+$

And now I'm trying to check for all the double symbols but I cannot go ahead successfully.

Thanks @AmalMurali, yes indeed `abcd"efg` has single double quote — anubhava, Aug 12 '14 at 13:57
I didn't wrote '**"**' but a double "**''**". Now does it make sense? — Ayeye Brazo, Aug 12 '14 at 13:57
Or better, double apostrophe is invalid, single quotation marks is invalid. single apostrophe is valid. — Ayeye Brazo, Aug 12 '14 at 13:59
Because I need **Mc'Millan, .jr** to be valid and no other alternatives. — Ayeye Brazo, Aug 12 '14 at 13:59
We are talking about why, why and why... but no one write a single line of regex here... I don't need regex suggestions I just need to solve my regex. — Ayeye Brazo, Aug 12 '14 at 14:00
Seems like you guys doen't have 2 different keyboard keys with ' and " to continue talking about it... — Ayeye Brazo, Aug 12 '14 at 14:02
People get many answers to a question that are easy to understand and have all the logic/rules clear. Do you seriously believe you question meets this criteria? — anubhava, Aug 12 '14 at 14:10

score 3 · Answer 1 · answered Aug 12 '14 at 13:26

3

It's a bad idea. There is no international list of allowed characters that people could use in their names. Some surnames even contain Unicode symbols — it will not be possible to write a regex that would perfectly validate all of them correctly. Even if you can come up with a regex, it might be too generic that it wouldn't be effective.

Read this article for why you shouldn't be doing this: Falsehoods Programmers Believe About Names

answered Aug 12 '14 at 13:26

Amal Murali

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I just need to create the regex I wrote above... Even if it is a bad idea. Thanks – Ayeye Brazo Aug 12 '14 at 13:30
I'll just quote [John](http://stackoverflow.com/a/888902/1438393): "*Step back and ask yourself what you are actually trying to accomplish. Then try to accomplish it without making any assumptions about what people's surnames are, or what they mean.*". – Amal Murali Aug 12 '14 at 13:31

score 2 · Accepted Answer · edited May 23 '17 at 12:11

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If after reading this insightful post by Amal Murali and you still want to do this with a regex, please see this:

/^(?![^'\-_\n]*['\-_][^'\-_\n]*['\-_])[a-z .',-_]+$/m

View a regex demo!

edited May 23 '17 at 12:11

Community

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answered Aug 12 '14 at 14:10

Unihedron

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And this doesn't match `abcd"efg` as valid (single double quote that is). Moreover `And now I'm trying to check for all the double symbols but I cannot go ahead successfully.` is matched using this regex as valid surname. – anubhava Aug 12 '14 at 14:20

Surname regular expression

2 Answers2