Balances tags of string using a modified stack.

Formats text for the editor.

Acts on text which is about to be edited.

Given a date in UTC or GMT timezone, returns that date in the timezone of the site.

Given a date in the timezone of the site, returns that date in UTC.

Retrieves the regular expression for an HTML element.

Extracts and returns the first URL from passed content.

Converts entities, while preserving already-encoded entities.

Determines the difference between two timestamps.

Verifies that an email is valid.