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<p class="MsoNormal"><span style="font-size:11.0pt">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I have come across this little nuisance when using agda especially when doing life hacking in lectures or talks.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I try to evaluate an expression which depends on opening some modules which I have opened in my file but agda is not aware of this. E.g.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">record Stream (A : Set) : Set where<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> constructor _</span><span style="font-size:11.0pt;font-family:"Cambria Math",serif">∷</span><span style="font-size:11.0pt">_<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> coinductive<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> field<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> hd : A<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> tl : Stream A<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">open Stream<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">from : </span><span style="font-size:11.0pt;font-family:"Cambria Math",serif">ℕ</span><span style="font-size:11.0pt"> → Stream
</span><span style="font-size:11.0pt;font-family:"Cambria Math",serif">ℕ</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">hd (from n) = n<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">tl (from n) = from (suc n)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">And then I say C-c C-n “hd (from 0)” and agda responds<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">1,1-3<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Not in scope:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> hd at 1,1-3 (did you mean 'Stream.hd'?)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">when scope checking hd<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Ok I can just introduce a shed
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">x = {!!}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">and evaluate inside there but this is a bit clumsy. Isn’t there a better way to do this?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Btw, for the same purposes I’d love to have an agda top-level! And a printer that evaluates conductive objects by mapping them to costrings…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thorsten<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">P.S. Ok I can say “open Stream public” – but do I want this?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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