I have been having issues with output filters, specifically 'isnot' (related to Bug #7029). So, I took a look at modoutputfilter.class.php and I found these lines at the top of the switch statement that handles output modifiers:
/* conditional operators */
/* @todo these conditionals should be removed because there are cleaner ways to do this now */
These lines were included in the initial commit of this file in 2009. I'm not sure what to make of this. Specifically which conditionals is this referring to, all of them? What cleaner ways are there of doing conditionals in MODX Tags? Or is this comment just totally irrelevant today?
That commit was by Jason. I wonder if he remembers, after 5 years, what it refers to.