String methods & normalization
Make text work for you
Lesson 9 of 20 · 8 min · Module 3: Collections & meaningful data
People type extra spaces and inconsistent capitalization. A small normalization function turns that input into a predictable form.
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By the end, you’ll be able to…
- Apply string methods without changing the original
- Understand why splitting can create empty values
- Handle empty input deliberately
The idea
Use trim() to remove outer whitespace, toLowerCase() for lowercase text, split(" ") for words, and join("-") to reconnect them.
const title = " Small Steps ";
console.log(title.trim().toLowerCase()); // small steps01Methods return new values
Strings are immutable. Calling trim does not rewrite the original variable. Use the returned string, either by storing it or by chaining another operation.
02Remove empty pieces
Splitting on one ordinary space creates empty strings when spaces repeat. Filter out those pieces before joining. This exercise is intentionally limited to ordinary spaces, not a full production URL sanitizer.
Your turn
slugify(title) to lowercase a title, trim its edges, and replace runs of ordinary spaces with one hyphen. An empty or space-only title returns an empty string.What the checks look for
- Normalizes a title
- Collapses extra ordinary spaces
- Handles empty text
Take this with you
Normalize input in small, explicit transformations.