Datatype Constructors: selector/matcher vs builder 'function'

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From this discussion 'Contexts on datatype declarations'
http://web.archive.org/web/20151208175102/http://code.haskell.org/~dons/haskell-1990-2000/threads.html#04062

It looks like (at least at the time) GHC had separate functions for
matching vs building using a constructor.

In Hugs, the type for a datatype's constructor(s) is inferred in static.c
routine selectCtxt( ) called from depConstrs( ).

The type for field (label) selectors is inferred in type.c routine typeSel(
). And it's easy enough to hack that to drop the preds on the selectors, as
SPJ advocates in that thread.

What I can't find is where Hugs infers the type for a data constructor
appearing in matching position.

Any hints?  Thanks in advance

AntC

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<div dir=3D"ltr"><div><font face=3D"arial, sans-serif"><br></font></div><fo=
nt face=3D"arial, sans-serif">From this discussion &#39;Contexts on datatyp=
e declarations&#39;</font><div><font face=3D"arial, sans-serif"><a href=3D"=
http://web.archive.org/web/20151208175102/http://code.haskell.org/~dons/has=
kell-1990-2000/threads.html#04062">http://web.archive.org/web/2015120817510=
2/http://code.haskell.org/~dons/haskell-1990-2000/threads.html#04062</a><br=
></font></div><div><font face=3D"arial, sans-serif"><br></font></div><div><=
font face=3D"arial, sans-serif">It looks like (at least at the time) GHC ha=
d separate functions for matching vs building using a constructor.</font></=
div><div><font face=3D"arial, sans-serif"><br></font></div><div><font face=
=3D"arial, sans-serif">In Hugs, the type for a datatype&#39;s constructor(s=
) is inferred in static.c routine selectCtxt( ) called from depConstrs( ).<=
/font></div><div><font face=3D"arial, sans-serif"><br></font></div><div><fo=
nt face=3D"arial, sans-serif">The type for field (label) selectors is infer=
red in type.c routine typeSel( ). And it&#39;s easy enough to hack that to =
drop the preds on the selectors, as SPJ advocates in that thread.</font></d=
iv><div><font face=3D"arial, sans-serif"><br></font></div><div><font face=
=3D"arial, sans-serif">What I can&#39;t find is where Hugs infers the type =
for a data constructor appearing in matching position.</font></div><div><fo=
nt face=3D"arial, sans-serif"><br></font></div><div><font face=3D"arial, sa=
ns-serif">Any hints?=C2=A0 Thanks in advance</font></div><div><font face=3D=
"arial, sans-serif"><br></font></div><div><font face=3D"arial, sans-serif">=
AntC</font></div><div><br></div></div>

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