How do you return all matching strings against a regular expression?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of JavaScript conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
The matchAll() method can be used to return an iterator of all results matching a string against a regular expression. For example, the below example returns an array of matching string results against a regular expression,
let regexp = /Hello(\d?)/g;
let greeting = "Hello1Hello2Hello3";
let greetingList = [...greeting.matchAll(regexp)];
console.log(greetingList[0][0]); //Hello1
console.log(greetingList[1][0]); //Hello2
console.log(greetingList[2][0]); //Hello3
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