How To Use Regex Negative Lookahead To Exclude Strings

I have a task in Perl to list specific files based on pattern match, those with and those without the string “_from_”. There are two files in the directory to filter: static-east.properties static-east_from_west.properties To capture the files with the _from_ string was easy:
1 |
/^static-(.*?)_from_(.*?)\.properties$/ |
To capture the files WITHOUT the _from_ string was not quite […]