What is a "trap"?

[2colours]

A side product of #3839

Hello,

sort of a vague, bikesheddy question, more for pondering slowly and more for long-term benefits.

There is probably no single characteristic to identify a "trap" but it would definintely help with convergence to consider at least a couple of guidelines regarding what might qualify as one.

To get some thoughts down for myself: I do not think something qualifies as a trap just because a newcomer may not know it or may be surprised by it. However, if we can expect newcomers to have a definite expectation that is contradicted, that might qualify as a trap. Also, the idea of "something that seems easy and obvious but in fact doesn't work" should be expressed some way. Another question would be if long-standing bugs should be trap candidates or not.