Zach Leatherman • 10/2/2025

I want to intercept Boolean Coercion for Objects in JavaScript

Read Original

The article details the author's attempt to create a custom Boolean-like object in JavaScript that can correctly evaluate to false when coerced. It explains MDN's warnings, tests with Symbol.toPrimitive and valueOf, and concludes that boolean coercion uniquely ignores user-defined methods, ending with a call for help from the ECMAScript community.

0 comments
#JavaScript #ecmascript #Boolean Coercion
I want to intercept Boolean Coercion for Objects in JavaScript

Comments

No comments yet

Be the first to share your thoughts!

Browser Extension

Get instant access to AllDevBlogs from your browser

Top of the Week

1
Using Browser Apis In React Practical Guide
Jivbcoop • 2 votes
2
Better react-hook-form Smart Form Components
Maarten Hus • 2 votes
3
Top picks — 2026 January
Paweł Grzybek • 1 votes
4
In Praise of –dry-run
Henrik Warne • 1 votes
5
Deep Learning is Powerful Because It Makes Hard Things Easy - Reflections 10 Years On
Ferenc Huszár • 1 votes
6
Vibe coding your first iOS app
William Denniss • 1 votes
7
AGI, ASI, A*I – Do we have all we need to get there?
John D. Cook • 1 votes
8
Quoting Thariq Shihipar
Simon Willison • 1 votes
9
Dew Drop – January 15, 2026 (#4583)
Alvin Ashcraft • 1 votes