How can you dynamically create regular expressions from user input strings using the RegExp object constructor?

Utilizing RegExp Object Constructor for Regular Expression Creation

In the context of designing a regular expression tester, where users input a regular expression as a string, converting it into a usable format poses a challenge. This is because if the user is not required to include the opening and closing slashes ('//') around the expression, they cannot specify flags such as 'g' and 'i'. However, including the slashes makes the input a string literal, preventing its direct conversion to a regular expression.

To address this, the RegExp object constructor provides a solution. By using its constructor syntax, you can create a regular expression object from a string:

var re = new RegExp("a|b", "i");

This method is equivalent to writing the regular expression directly with the required flags:

var re = /a|b/i;

By utilizing the RegExp object constructor, you can effectively convert user input strings into regular expressions, allowing them to specify flags and use the resulting objects in your testing program. This approach eliminates the need for manual parsing of the string and flags, simplifying the process of creating regular expressions from user inputs.

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