Matching FFI types with "match"

[Peter Samarin]

Hi all,

Is this behavior expected?

(require racket/main

            ffi/unsafe)

(for/list ([type (list _float _double _int)])
  (match type
    [_float 'float]
    [_double 'double]
    [_int 'int]))

> '(float float float)

I was expecting '(float double int)

--Peter

[Sam Tobin-Hochstadt]

Yes, the problem here is that plain names in `match` are bindings, not
comparisons to things in the environment. So if you replace `_float`
with `empty` or `string=?` it will still produce the same answer.

If you want to compare with something in a `match` pattern, you might
want `==`: https://docs.racket-lang.org/reference/match.html?q=%3D%3D#%28form._%28%28lib._racket%2Fmatch..rkt%29._~3d~3d%29%29

Sam

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[Peter Samarin]

Thank you, that was helpful!