I'm trying to get matches on a string in Unity using a Regular Expressions pattern. I've written the whole code inside a sample project and it worked perfectly fine.
tokens[line] = Regex.Matches(instructionLines[line], "^\\w*|(?<=q\\[)\\d*(?=\\]))";
I have validated that it matches what I need with regex101.
I have then printed out the result in my console, which was also correct.
Console App:
h 0
h 1
h 2
h 3
cx 1 2
t 1
Finally, I copy-pasted the code in Unity - and it doesn't match the first word of the line like it did in the sample project.
Unity Console:
0
1
2
3
1 2
1
I didn't change anything, the imports are the same (using System.Text.RegularExpressions;) and the regex is correct. Why does Unity do this, and how do I fix this incorrect behaviour?
The issue was fixed thanks to @Thefourthbird, to quote from comments:
Try it adding multiline (?m)^[a-z]|(?<=q[)\d(?=])
In the link you added to your question regex101.com/r/FzpZXq/1 you can see at the right top that there is an m flag for multiline. As your pattern uses an anchor ^ you have to enable multiline, which can also be done using an inline modifier (?m) See regular-expressions.info/anchors.html