// This tests whether a pattern matches a string.
let match = /p([a-z]+)ch/.test("peach");
console.log(match);

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

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

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

// This also finds the first match but returns the
// start and end indexes for the match instead of the
// matching text.
let result = "peach punch".search(r);
console.log("idx:", result);

// The `exec` method returns information about both the
// whole-pattern matches and the submatches within those matches.
let execResult = r.exec("peach punch");
console.log(execResult);

// The `matchAll` method returns an iterator of all matches
// in the input, not just the first.
let str = "peach punch pinch";
let matches = str.matchAll(r);
for (const match of matches) {
    console.log(match);
}

// Providing a non-negative integer as the second
// argument to `match` will limit the number of matches.
console.log(str.match(r));

// The `replace` method can be used to replace
// subsets of strings with other values.
console.log("a peach".replace(r, "<fruit>"));

// The second argument to `replace` can also be a function
// that transforms the matched text.
console.log("a peach".replace(r, (match) => match.toUpperCase()));