Programmers fallacies about postcodes:
A postcode covers a small geographic area
A postcode is good enough to locate an end user for generating location suggestions
A postcode will be in a single timezone
A postcode only has a single state
A postcode has no exclaves/enclaves
I would like you to meet 0872. Australia's largest postcode (I think), covers 3 states, has three cut outs (Warbuton, Alpurrurulam, and Alice Springs), and even still some mail outside of this area is routed via 0872
Additional fallacies about postcodes:
A postcode can be treated as a number (0872 would become 872)
A postcode can be mapped to other geographic coding schemes like LGAs
A postcode can't move or change
A postcode can be mapped to a geographical location (see e.g. defence force personnel codes, or 9999 postcode for โNorth Pole, VICโ)
(via https://cloudisland.nz/@xssfox/111175045856469207)