How to dial in a regex to detect @usernames

I have a regex that I've just realized isn't precise enough. Right now I'm using:

let regex = try NSRegularExpression(pattern: "@[^\s]+")

Which on the following string: let str = "@alice, @bob, @zack@example.com sara@example.com"

Is returning["@alice,", "@bob,", "@zack@example.com", "example.com"] (notice the commas inside of some of the array elements)

How can I make this more precise so it grabs "@alice" and "@bob" without the trailing comma and ignores the latter 2 examples?

Thanks

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

Would this: @[^\s]+?(?=,) work for you? test

– cybernetic.nomad
Jan 2 at 22:19

add a comment |

I have a regex that I've just realized isn't precise enough. Right now I'm using:

let regex = try NSRegularExpression(pattern: "@[^\s]+")

Which on the following string: let str = "@alice, @bob, @zack@example.com sara@example.com"

Is returning["@alice,", "@bob,", "@zack@example.com", "example.com"] (notice the commas inside of some of the array elements)

How can I make this more precise so it grabs "@alice" and "@bob" without the trailing comma and ignores the latter 2 examples?

Thanks

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

Would this: @[^\s]+?(?=,) work for you? test

– cybernetic.nomad
Jan 2 at 22:19

add a comment |

I have a regex that I've just realized isn't precise enough. Right now I'm using:

let regex = try NSRegularExpression(pattern: "@[^\s]+")

Which on the following string: let str = "@alice, @bob, @zack@example.com sara@example.com"

Is returning["@alice,", "@bob,", "@zack@example.com", "example.com"] (notice the commas inside of some of the array elements)

How can I make this more precise so it grabs "@alice" and "@bob" without the trailing comma and ignores the latter 2 examples?

Thanks

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

I have a regex that I've just realized isn't precise enough. Right now I'm using:

let regex = try NSRegularExpression(pattern: "@[^\s]+")

Which on the following string: let str = "@alice, @bob, @zack@example.com sara@example.com"

Is returning["@alice,", "@bob,", "@zack@example.com", "example.com"] (notice the commas inside of some of the array elements)

How can I make this more precise so it grabs "@alice" and "@bob" without the trailing comma and ignores the latter 2 examples?

Thanks

ios swift regex

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

asked Jan 2 at 22:16

Zack Shapiro

1,17594284

Would this: @[^\s]+?(?=,) work for you? test

– cybernetic.nomad
Jan 2 at 22:19

add a comment |

Would this: @[^\s]+?(?=,) work for you? test

– cybernetic.nomad
Jan 2 at 22:19

Would this: @[^\s]+?(?=,) work for you? test

– cybernetic.nomad
Jan 2 at 22:19

add a comment |

1 Answer
1

active

oldest

votes

You may use

let regex = try NSRegularExpression(pattern: "\B@[^@\s]+\b(?!@\w)")

See the regex demo.

It will match

B@ - a @ not preceded with a letter, digit or _

[^@s]+ - 1+ chars other than @ and whitespace

b - a word boundary

(?!@w) - no @ followed with a letter, digit or _ is allowed immediately to the right of the current location. A (?!@) might suffice though.

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

This works well. Thanks Wiktor. Appreciate it. Is it possible to slightly modify so it ensures that the @name is proceeded by a space and nothing else?

– Zack Shapiro
Jan 2 at 22:42

@ZackShapiro Replace B with (?<!S), "(?<!\S)@[^@\s]+\b(?!@\w)"

– Wiktor Stribiżew
Jan 2 at 22:55

@ZackShapiro If it worked for you please consider accepting/upvoting the answer.

– Wiktor Stribiżew
Jan 3 at 7:42

Thanks for your help, Wiktor. Have a good day!

– Zack Shapiro
Jan 3 at 15:19

add a comment |

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1 Answer
1

active

oldest

votes

1 Answer
1

active

oldest

votes

You may use

let regex = try NSRegularExpression(pattern: "\B@[^@\s]+\b(?!@\w)")

See the regex demo.

It will match

B@ - a @ not preceded with a letter, digit or _

[^@s]+ - 1+ chars other than @ and whitespace

b - a word boundary

(?!@w) - no @ followed with a letter, digit or _ is allowed immediately to the right of the current location. A (?!@) might suffice though.

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

This works well. Thanks Wiktor. Appreciate it. Is it possible to slightly modify so it ensures that the @name is proceeded by a space and nothing else?

– Zack Shapiro
Jan 2 at 22:42

@ZackShapiro Replace B with (?<!S), "(?<!\S)@[^@\s]+\b(?!@\w)"

– Wiktor Stribiżew
Jan 2 at 22:55

@ZackShapiro If it worked for you please consider accepting/upvoting the answer.

– Wiktor Stribiżew
Jan 3 at 7:42

Thanks for your help, Wiktor. Have a good day!

– Zack Shapiro
Jan 3 at 15:19

add a comment |

You may use

let regex = try NSRegularExpression(pattern: "\B@[^@\s]+\b(?!@\w)")

See the regex demo.

It will match

B@ - a @ not preceded with a letter, digit or _

[^@s]+ - 1+ chars other than @ and whitespace

b - a word boundary

(?!@w) - no @ followed with a letter, digit or _ is allowed immediately to the right of the current location. A (?!@) might suffice though.

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

This works well. Thanks Wiktor. Appreciate it. Is it possible to slightly modify so it ensures that the @name is proceeded by a space and nothing else?

– Zack Shapiro
Jan 2 at 22:42

@ZackShapiro Replace B with (?<!S), "(?<!\S)@[^@\s]+\b(?!@\w)"

– Wiktor Stribiżew
Jan 2 at 22:55

@ZackShapiro If it worked for you please consider accepting/upvoting the answer.

– Wiktor Stribiżew
Jan 3 at 7:42

Thanks for your help, Wiktor. Have a good day!

– Zack Shapiro
Jan 3 at 15:19

add a comment |

You may use

let regex = try NSRegularExpression(pattern: "\B@[^@\s]+\b(?!@\w)")

See the regex demo.

It will match

B@ - a @ not preceded with a letter, digit or _

[^@s]+ - 1+ chars other than @ and whitespace

b - a word boundary

(?!@w) - no @ followed with a letter, digit or _ is allowed immediately to the right of the current location. A (?!@) might suffice though.

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

You may use

let regex = try NSRegularExpression(pattern: "\B@[^@\s]+\b(?!@\w)")

See the regex demo.

It will match

B@ - a @ not preceded with a letter, digit or _

[^@s]+ - 1+ chars other than @ and whitespace

b - a word boundary

(?!@w) - no @ followed with a letter, digit or _ is allowed immediately to the right of the current location. A (?!@) might suffice though.

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

answered Jan 2 at 22:19

Wiktor Stribiżew

327k16147226

This works well. Thanks Wiktor. Appreciate it. Is it possible to slightly modify so it ensures that the @name is proceeded by a space and nothing else?

– Zack Shapiro
Jan 2 at 22:42

@ZackShapiro Replace B with (?<!S), "(?<!\S)@[^@\s]+\b(?!@\w)"

– Wiktor Stribiżew
Jan 2 at 22:55

@ZackShapiro If it worked for you please consider accepting/upvoting the answer.

– Wiktor Stribiżew
Jan 3 at 7:42

Thanks for your help, Wiktor. Have a good day!

– Zack Shapiro
Jan 3 at 15:19

add a comment |

This works well. Thanks Wiktor. Appreciate it. Is it possible to slightly modify so it ensures that the @name is proceeded by a space and nothing else?

– Zack Shapiro
Jan 2 at 22:42

@ZackShapiro Replace B with (?<!S), "(?<!\S)@[^@\s]+\b(?!@\w)"

– Wiktor Stribiżew
Jan 2 at 22:55

@ZackShapiro If it worked for you please consider accepting/upvoting the answer.

– Wiktor Stribiżew
Jan 3 at 7:42

Thanks for your help, Wiktor. Have a good day!

– Zack Shapiro
Jan 3 at 15:19

This works well. Thanks Wiktor. Appreciate it. Is it possible to slightly modify so it ensures that the @name is proceeded by a space and nothing else?

– Zack Shapiro
Jan 2 at 22:42

@ZackShapiro Replace B with (?<!S), "(?<!\S)@[^@\s]+\b(?!@\w)"

– Wiktor Stribiżew
Jan 2 at 22:55

@ZackShapiro If it worked for you please consider accepting/upvoting the answer.

– Wiktor Stribiżew
Jan 3 at 7:42

Thanks for your help, Wiktor. Have a good day!

– Zack Shapiro
Jan 3 at 15:19

add a comment |

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