Prompt Title: Regex for Filtering Data.

Here's a valid JavaScript regular expression that matches all occurrences of filter=15/0/* and captures the first numeric value in a group:

javascriptCopy code
/filter=([0-9]+)\/0\/\*/

Explanation:

• / is the starting delimiter for the regular expression
• filter= matches the literal string "filter="
• ([0-9]+) is a capturing group that matches one or more digits (the + quantifier means "one or more")
• \/0\/\* matches the literal string "/0/*", with each slash and asterisk escaped by a backslash
• / is the ending delimiter for the regular expression

This regular expression uses character classes ([0-9]) to match any digit, and the + quantifier to match one or more occurrences of the digit. The parentheses around [0-9]+ create a capturing group that captures the first numeric value in the input string. The backslashes before the slashes and asterisk escape those characters so that they are treated literally in the regular expression.