5 ms·

> "Null: the billion dollar mistake" That was in C, release 52 years ago. > JavaScript [...] doubled it by having yet another null-ish value. And did so 24 y

by cies 2y ago

> "Null: the billion dollar mistake" That was in C, release 52 years ago. > JavaScript [...] doubled it by having yet another null-ish value. And did so 24 years later! In defense of JS they supposedly designed and implemented the language in 10 days. I find "implicit nulls" less defensible for Golang (38 years after C) and Java (23 years after C), as they had plenty of time to learn from other's mistakes.

azornathogron 2y ago
> That was in C, release 52 years ago No, it was in ALGOL W. The "billion dollar mistake" is what Tony Hoare - one of the designers of the language - called it (later on, of course).
- DemocracyFTW2 2y ago
  > "billion dollar mistake" is what Tony Hoare [...] called it (later on, of course) would be damning but also fun if it ever turned out they planted this as a practical joke, fully knowing what they were doing
afiori 2y ago
The billion dollars mistake is not having nulls, you need some concept of null. The mistake was allowing nulls to be a valid value for all pointers/reference at the type level. You cannot make this mistake in an untyped language like JavaScript* The solution to this is not eliminating nulls but rather separating nullable pointers/references from non-nullable ones * Ok ironically JavaScript has an actual historical implementation bug where typeof null === "object" (basically Netscape used tagged pointers, the object tag was 0, and null was represented as a null pointer, so typeof would read the tag and return "object"
- cies 2y ago
  > The billion dollars mistake is not having nulls, you need some concept of null. > The mistake was allowing nulls to be a valid value for all pointers/reference at the type level. Hence I call it "implicit nulls" in my post. I know `null` as a concept is important, even if you have it as `Unit`, `Void` or `Nothing`. You are totally right thought that in languages that do not force you to specify types it is basically needed as you cannot hint a type to begin with.

by cies 2y ago

azornathogron 2y ago

> That was in C, release 52 years ago No, it was in ALGOL W. The "billion dollar mistake" is what Tony Hoare - one of the designers of the language - called it (later on, of course).

DemocracyFTW2 2y ago
> "billion dollar mistake" is what Tony Hoare [...] called it (later on, of course) would be damning but also fun if it ever turned out they planted this as a practical joke, fully knowing what they were doing

afiori 2y ago

The billion dollars mistake is not having nulls, you need some concept of null. The mistake was allowing nulls to be a valid value for all pointers/reference at the type level. You cannot make this mistake in an untyped language like JavaScript* The solution to this is not eliminating nulls but rather separating nullable pointers/references from non-nullable ones * Ok ironically JavaScript has an actual historical implementation bug where typeof null === "object" (basically Netscape used tagged pointers, the object tag was 0, and null was represented as a null pointer, so typeof would read the tag and return "object"

cies 2y ago
> The billion dollars mistake is not having nulls, you need some concept of null. > The mistake was allowing nulls to be a valid value for all pointers/reference at the type level. Hence I call it "implicit nulls" in my post. I know `null` as a concept is important, even if you have it as `Unit`, `Void` or `Nothing`. You are totally right thought that in languages that do not force you to specify types it is basically needed as you cannot hint a type to begin with.