Wiki about apostrophes

[kstarikov]

In https://github.com/Frege/frege/wiki/LYAH-adaptions-for-Frege#babys-first-functions-subject-to-review-by-mmhelloworld :

In Frege, the apostrophe is only allowed at the end of a name

But in Frege repl (version 3.24.30) it looks as follows:

frege> conanOBrien' = "It's a-me, Conan O'Brien!"
function conanOBrien' :: String

frege> conanOBrien'
java.lang.NoSuchFieldException: conanOBrien'

By the way, having the apostrophe in the middle of the name leads to the same results:

frege> conanO'Brien = "It's a-me, Conan O'Brien!"
function conanO'Brien :: String

frege> conanO'Brien
java.lang.NoSuchFieldException: conanO'Brien

However, if I define it as a function with an argument, it works:

frege> conanO'Brien a = "It's a-me, Conan O'Brien!" ++ a
function conanO'Brien :: String -> String

frege> conanO'Brien "foo"
It's a-me, Conan O'Brien!foo

[Ingo60]

This looks like a bug in the REPL, it also appears in the online REPL.

However,

conanO'Brian = "foo"
id conanO'Brian 

does work.

Needs more investigation.

[mmhelloworld]

I am investigating on the REPL side.

[mmhelloworld]

Ok, I am confirming that this is REPL bug. For conanOBrien', compiler is generating a field with name conanOBrien$tick. When we just evaluate the field with frege> conanOBrien', REPL is trying to evaluate the field value by looking up the field on the generated class using reflection with name conanOBrien' hence the NoSuchFieldException.

With conanO'Brien a function case and id conanO'Brian case, REPL is not directly interpreting conanO'Brien but the result of those expressions so these cases succeed.