Re: TR issue with the type of expt
Tim Brown <[email protected]>
| Newsgroups | gmane.comp.lang.racket.user,gmane.lisp.scheme.plt |
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| Message-ID | <[email protected]> |
/i/ forgot about that. And there you have it: (-> Nonnegative-Real Real Real) Don’t laugh, but the irony (tragedy) is that I’m using it to implement some quaternion stuff. On 27/09/16 14:43, Pierpaolo Bernardi wrote: > On Tue, Sep 27, 2016 at 3:23 PM, Tim Brown <[email protected]> wrote: > >> I believe (because I can’t think of a counterexample) that >> (expt Real Real) is never Complex; and therefore expt can be of type >> (Real Real -> Real). > > What about (expt -1 1/2) ? > -- Tim Brown CEng MBCS <[email protected]> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ City Computing Limited · www.cityc.co.uk City House · Sutton Park Rd · Sutton · Surrey · SM1 2AE · GB T:+44 20 8770 2110 · F:+44 20 8770 2130 ──────────────────────────────────────────────────────────────────────── City Computing Limited registered in London No:1767817. Registered Office: City House, Sutton Park Road, Sutton, Surrey, SM1 2AE VAT No: GB 918 4680 96 -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.