Add get-failure-result to racket/function
#4854
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| (if (procedure-arity-includes? v 0) | ||
| (v) | ||
| (raise-argument-error 'get-failure-result | ||
| "a procedure that accepts 0 non-keyword arguments" |
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This should use (procedure-arity-includes/c 0) as the contract string, I think.
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The intent here may have been to match the exception raised by hash-ref. It needs to different, though, to do that. The hash-ref function conceptually always applies a procedure failure result to 0 arguments, but it improves the exn:fail:contract:arity error message.
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The error message is based on the one produced by failure-result/c, which is really just the error message produced by (-> any). I’m happy to change it, if desired, but consistency with failure-result/c seemed logical.
I have also written this function multiple times, but I think I have rarely if ever implemented an explicit arity check. That seems quite useful for cases when the argument isn't already protected by |
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This adds a very simple function named
get-failure-resulttoracket/function. It is essentially justexcept that the version in this PR also includes an explicit arity check.
Since this function is so simple, the convenience it affords is obviously extremely minor. Still, I’ve written it so many times that it feels worth putting somewhere, especially since we already have
failure-result/c.