<br><font size=2 face="sans-serif">Hello,</font>
<br>
<br><tt><font size=2>> > Just a bit of minor academic nitpicking...
<br>
> > <br>
> > > Yeah. After all, the "uniqueness constraint"
has a theory with an<br>
> > > excellent pedigree (IIUC linear logic, whose proof theory
Clean uses<br>
> > > here, goes back at least to the 60s, and Wadler proposed
linear<br>
> > types<br>
> > > for IO before anybody had heard of monads). <br>
> > > <br>
> > Linear logic/typing does not quite capture uniqueness types since
a<br>
> > term with a unique type can always be copied to become non-unique,
but<br>
> > a linear type cannot become unrestricted. <br>
> <br>
> Can I write a Clean program with a function that duplicates World?<br>
> <br>
Clean won't let you duplicate the World. My comment on the mismatch with
linear logic is aimed more at general uniqueness type systems (e.g. </font></tt><font size=3>recent
work by de Vries, Plasmeijer, and Abrahamson such as https://www.cs.tcd.ie/~devriese/pub/ifl06-paper.pdf).
Sorry for the confusion.</font>
<br>
<br><font size=3>-Jeff</font>
<br>
<br>
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