In this letter, Dijkstra talks about readability and maintainability in a time where those topics were rarely talked about (1968). This letter was one of the main causes why modern programmers don’t have to trouble themselves with goto statements. Older languages like Java and C# still have a (discouraged) goto statement, because they (mindlessly) copied it from C, which (mindlessly) copied it from Assembly, but more modern languages like Swift and Kotlin don’t even have a goto statement anymore.
switch statements are three gotos in a trenchcoat.
Anything is a goto in disguise when you think about it
In most CPU instruction sets, the only conditional instruction is branch (aka goto).
And after each instruction, the CPU go to the next instruction
Duff’s device takes this to a whole new level.
This is very nice and clean
Egads! My eyes.
I’d rather it was just written in assembly. It’s the
do {
opening a block under thecase 0
, but then proceeding to have furthercase
statements inside that block. You now have case statements in two different scopes that are part of the same switch.