Regular Expressions (js) | Chinese Rule of Eight

new style

1	const re1 = new RegExp('hey')

literal style

1	const req = /hey/;

test

const req = /hey/;

var res = req.test('hadooo hey!');

console.log(res); // true

var res2 = req.test('sho ryu key!');

console.log(res2); // false

var res3 = req.test('ayiii ya hii hiiii');

console.log(res3); // false

replace

let result = "shooo ryu ken ryu Ryu rYu ryU!".replace(/ryu/gi, function(str, offset, s){

console.log(`Found "${str}" at position ${offset} in string "${s}"`);

return str.toLowerCase();

});

console.log('After replacement: ' + result);

Found “ryu” at position 6 in string “shooo ryu ken ryu Ryu rYu ryU!”
Found “ryu” at position 14 in string “shooo ryu ken ryu Ryu rYu ryU!”
Found “Ryu” at position 18 in string “shooo ryu ken ryu Ryu rYu ryU!”
Found “rYu” at position 22 in string “shooo ryu ken ryu Ryu rYu ryU!”
Found “ryU” at position 26 in string “shooo ryu ken ryu Ryu rYu ryU!”

After replacement: shooo ryu ken ryu ryu ryu ryu!