According to https://www.kamailio.org/wikidocs/cookbooks/devel/core/ (Core Cookbook) type boolean is documented as:
* boolean - aliases to 1 (true, on, yes) or 0 (false, off, no)
Moreover the if() and while() statement can accept a number as condition. My expectation was that passing non-zero is always converted to true, but this is not correct.
Please document how numbers are converted to booleans in case of if() and while() conditions.