use Regex;
use IO;

proc main() {
    // This tests whether a pattern matches a string.
    var match = "peach".matches(re"p([a-z]+)ch");
    writeln(match);

    // For other regexp tasks, you'll need to create a Regex object.
    var r = re"p([a-z]+)ch";

    // Many methods are available on these objects. Here's
    // a match test like we saw earlier.
    writeln(r.matches("peach"));

    // This finds the match for the regexp.
    writeln(r.match("peach punch"));

    // This also finds the first match but returns the
    // start and end indexes for the match instead of the
    // matching text.
    var (start, end) = r.find("peach punch");
    writeln("idx: ", start, "..", end);

    // The `captures` method includes information about
    // both the whole-pattern matches and the submatches
    // within those matches.
    var captures = r.captures("peach punch");
    writeln(captures);

    // To find all matches for a regexp:
    var allMatches = r.matches("peach punch pinch");
    writeln(allMatches);

    // Providing a non-negative integer as the maxCount
    // argument to these functions will limit the number
    // of matches.
    allMatches = r.matches("peach punch pinch", maxCount=2);
    writeln(allMatches);

    // The Regex module can also be used to replace
    // subsets of strings with other values.
    var replaced = r.sub("a peach", "<fruit>");
    writeln(replaced);

    // The `sub` method allows you to transform matched
    // text with a given function.
    replaced = r.sub("a peach", (m) => m.toUpper());
    writeln(replaced);
}