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Comment by perihelions | Hacker News Reader

SICP uses Scheme. Racket is a rather different, much larger language.

Racket's default #lang isn't even compatible with SICP -- for example its cons cells aren't mutable. (Though it's perfectly fine to use Racket tooling with SICP or other Scheme books -- just set #lang scheme instead of #lang racket).

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Dr. Racket does have an SICP #lang available; I'm not sure whether I got it through the package manager, or elsewhere.

https://docs.racket-lang.org/sicp-manual/Installation.html - Installation instructions.

Looks like a third-party package?

https://docs.racket-lang.org/sicp-manual/index.html

Racket still has mutable cons though. Just prefix everything with an `m`.

https://docs.racket-lang.org/reference/mpairs.html

I had been combining in rnrs/mutable-pairs-6 when I needed mutable cons, I didn't realize they were available in the base language. Dangit.

Thank you. I did not know that. I thought Racket was a superset of Scheme with a lot of batteries included.

You can very easily use Racket for SICP with minimal translations, even without the `#lang sicp` package. Racket's default cons cells aren't mutable, but Racket still has them. The `#lang sicp` package mainly provides the drawing needs that SICP uses as well as defaults for the MIT Scheme used in the book.

https://blog.racket-lang.org/2007/11/getting-rid-of-set-car-...

https://docs.racket-lang.org/reference/mpairs.html

Cheers mate.

That is how it started, as Dr. Scheme, then it decided to go its own way and they decided a new name to make this visible.

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