in reply to Re: Making JSON::{PP,XS} not decode true/false to JSON::{PP,XS}::Boolean objects
in thread Making JSON::{PP,XS} not decode true/false to JSON::{PP,XS}::Boolean objects

I'm afraid not, filter_json_object will only be called for JSON object (hash). There's also filter_json_single_key_object which is even more selective (called for JSON objects having a single key with a specific name). There's no filter mechanism in JSON that calls a callback for a boolean value.
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