Join Regex Expression Array

Question

I have an array of words e.g. apple, banana, horse which I want to have in a later function as split points.

I found this how to concat regex expressions, but it is for a fixed number of expressions: How can I concatenate regex literals in JavaScript?

Question: How to join an array of regex expressions?

filterTemp = [];
for (i = 0, len = filterWords.length; i < len; i++) {
  word = filterWords[i];
  filterTemp.push(new RegExp("\b" + word + "\b"));
}
filter = new RegExp(filterTemp.source.join("|"), "gi");
return console.log("filter", filter);

filterTemp.push(new RegExp("\\b" + word + "\\b"));

Avinash Raj
– Avinash Raj

2015-03-24 09:25:34 +00:00
Commented Mar 24, 2015 at 9:25 — Avinash Raj
– Avinash Raj, Commented Mar 24, 2015 at 9:25

anubhava · Accepted Answer · 2015-12-07 21:39:58Z

3

You don't need to construct RegExp inside loop just keep pushing strings into temp array and then use join only once outside to construct RegExp object:

var filterWords = ['abc', 'foo', 'bar'];
var filterTemp = [];
for (i = 0, len = filterWords.length; i < len; i++) {
  filterTemp.push("\\b" + filterWords[i] + "\\b");
}

filter = new RegExp(filterTemp.join("|"), "gi");
console.log("filter", filter);
//=> /\babc\b|\bfoo\b|\bbar\b/gi

edited Dec 7, 2015 at 21:39

answered Mar 24, 2015 at 9:33

anubhava

790k67 gold badges603 silver badges671 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Ryan Killeen Over a year ago

Just a note that filter = new RegExp(filterTemp.source.join("|"), "gi"); should be filter = new RegExp(filterTemp.join("|"), "gi");

gormonn · Accepted Answer · 2022-01-31 11:39:13Z

1

In 2022:

const validate = (val: string) => {
  const errorMessage =
    'Enter the time separated by commas. For example: 12:30, 22:00, ... etc.';
  const values = val.split(',').map((val: string) => val.trim());
  const filter = new RegExp(/^([0-1]?[0-9]|2[0-3]):[0-5][0-9]$/);
  const isValid = values.some(
    (value: string) => !filter.test(value),
  );
  return !isValid || errorMessage;
}

answered Jan 31, 2022 at 11:39

gormonn

315 bronze badges

Collectives™ on Stack Overflow

Join Regex Expression Array

2 Answers 2

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related