Match an expression as a list

Question

I have a string that I am trying to create a regular expression to match the assignment name "People" and its list of people

People = "Alice", "Bob", "Charlie", "David", "Erica", "Fred";

Conditions:

The expression name "People" must be returned
Any number of names must be returned separately (in groups)

I have looked to see if I could find something similar Match list of words without the list of chars around But I am not sure if this is the correct thing, or how to apply it.

The Regex expression I have tried

( \"([A-Z0-9]+)\",?)

This seems to match all of the individual names, however I am not sure how I can retrieve "People" in a separate group.

Is this a case for lookaround expressions in Regex? If so, how can it be implemented?

A capture group can only return one value. You need to do this in two steps: Step 1 retrieve People and the entire list of names as 2 groups. Step 2 split up the list of names. — Barmar, Jul 18 '22 at 12:55
Besides pulling these values; would you need to validate that the input is exactly as given structure? — JvdV, Jul 18 '22 at 13:02
@WiktorStribiżew Yes, that would work, however it doesn't satisfy the condition of returning the Expression name "People". — craig1231, Jul 18 '22 at 13:22

The fourth bird · Accepted Answer · 2022-07-18T19:21:43.953

You could make the pattern even more specific, but in this case you might use the CapturesCollection in C# by using a repeated capture group:

\b(?<name>[A-Za-z0-9]+)\s*=\s*(?:\"(?<people>[A-Za-z0-9]+)\",?\s*)+;

Regex demo | C# demo

Example to get the values:

string pattern = @"\b(?<name>[A-Za-z0-9]+)\s*=\s*(?:\""(?<people>[A-Za-z0-9]+)\"",?\s*)+;";
string input = @"People = ""Alice"", ""Bob"", ""Charlie"", ""David"", ""Erica"", ""Fred"";";
Match match = Regex.Match(input, pattern);
var name = match.Groups["name"].Value;
var strings = match.Groups["people"].Captures.Select(c => c.Value);

Console.WriteLine(name);

foreach (String s in strings)
{
    Console.WriteLine("-> "+ s);
}

Output

People
-> Alice
-> Bob
-> Charlie
-> David
-> Erica
-> Fred

Match an expression as a list

1 Answers1