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"path": "/t/haskells-missing-mutable-reference-type/14248#post_15",
"publishedAt": "2026-06-10T07:00:46.000Z",
"site": "https://discourse.haskell.org",
"tags": [
"A reference implementation of IOScopedRef"
],
"textContent": "I’m still not quite sure what you mean. Yes, `withIOScopedRef` in particular, and `IOScopedRef` in general, is a feature I am arguing for! Part of its essential behaviour is to allow references to be allocated dynamically, just like an essential feature of `IORef` is that they can be allocated dynamically.\n\nBut suppose I had your `contextual`. I could define\n\n\n contextual vault :: Contextual Vault\n contextual vault = Vault.empty\n\n\nto reconcile my interface with your implementation, couldn’t I?\n\n(This is essentially what A reference implementation of IOScopedRef suggests: _one_ global contextual variable, which is a vault.)",
"title": "Haskell's missing mutable reference type"
}