3676 words / 4 links / 3 images / 3 snippets
Duality is technical jargon for “complementary”. Programmers often overlook
the role dualities in programming and hence fail to recognize them, even if
they are hiding in plain sight. In this article we focus on two important pairs
of dual concepts: producers and consumers, sum types and product types. I also
spend some time ranting about default values being as bad as null values.