A dict? question

[Yury Bulka]

Dear Racketeers,

I have noticed something I don't understand:

> (dict? '(yay))
#f
> (dict? '('yay))
#t
> (dict-ref '('yay) 'yay)
; dict-ref: no value for key: 'yay in: '('yay)

I'm puzzled - what makes '('yay) a dict compared to '(yay)?

(Running Racket 7.8 on Linux).

--
Yury Bulka
https://mamot.fr/@setthemfree
#NotOnFacebook

[William J. Bowman]

try (dict-ref ‘(‘yay) ‘quote)

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> On Feb 27, 2021, at 15:31, Yury Bulka <setth...@privacyrequired.com> wrote:
>
> Dear Racketeers,

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[Yury Bulka]

Indeed,

> (dict-keys '('yay))
'(quote)
> (dict-values '('yay))
'((yay))
> (dict-ref '('yay) 'quote)
'(yay)

So... this boils down to:

> (equal? '('yay) '((quote yay)))
#t

--
Yury Bulka
https://mamot.fr/@setthemfree
#NotOnFacebook

[William J. Bowman]

Exactly. `'e` is a reader macro that gets read as `(quote e)`.
When it's already under a quote, the quoted quote is treated as a symbol:

> (dict-ref '('yay) 'quote)
'(yay)

> (quote ((quote yay)))
'('yay)
> '((quote yay))
'('yay)
> (dict-ref '((quote yay)) 'quote)
'(yay)

--
William J. Bowman

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