Find Characters with Lazy Matching
In regular expressions, a greedy match finds the longest possible part of a string that fits the regex pattern and returns it as a match. The alternative is called a lazy match, which finds the smallest possible part of the string that satisfies the regex pattern.
You can apply the regex /t[a-z]*i/
to the string "titanic"
. This regex is basically a pattern that starts with t
, ends with i
, and has some letters in between.
Regular expressions are by default greedy, so the match would return ["titani"]
. It finds the largest sub-string possible to fit the pattern.
However, you can use the ?
character to change it to lazy matching. "titanic"
matched against the adjusted regex of /t[a-z]*?i/
returns ["ti"]
.
Note: Parsing HTML with regular expressions should be avoided, but pattern matching an HTML string with regular expressions is completely fine.
Fix the regex /<.*>/
to return the HTML tag <h1>
and not the text "<h1>Winter is coming</h1>"
. Remember the wildcard .
in a regular expression matches any character.
Tests
- Waiting: 1. The
result
variable should be an array with<h1>
in it - Waiting: 2.
myRegex
should use lazy matching - Waiting: 3.
myRegex
should not include the stringh1
/** * Your test output will go here */