Don’t use the conditional query tags (i…

Don’t use the conditional query tags (is_page, is_post(), is_*) prior to init. In 3.0 and earlier, this merely failed quietly. In 3.1 this will produce a fatal error. We’ll workaround the fatal error prior to the release of 3.1, but in the meantime we’ll leave it to serve as a flag for improper use of the query conditionals. If you see a fatal error of the form “Call to a member function is_*() on a non-object” then a pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party or theme is using that function prior to init. See ticket 14729.

#3-1, #dev-notes