Racket v6.12 Released | Hacker News Reader

Racket v6.12 Released

blog.racket-lang.org

4 pointsMichaelBurge3 comments

Out of curiosity, why do alot (all?) of the objects in the built-in library have a % after them? Is that for convention or is that required? It seems like convention (since I see <%> also), but I can't tell for certain.

It's in their style guide. https://docs.racket-lang.org/style/Textual_Matters.html#%28p...

something% is a class.

something<%> is an interface

It's only convention. You could create your own and name them as you want. More info in http://docs.racket-lang.org/style/Textual_Matters.html#%28pa...

Only the things that start with # are special, because it may invoke some special part of the reader. There are too many of them. A few as examples:

  #o11 ;(octal)  ==>  9
  #e11 ;(exact)  ==> 11
  #i11 ;(inexact)==> 11.0

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