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boundary="f403043bb158a5337c056375061f" Subject: Re: [Caml-list] Are record types generative? --f403043bb158a5337c056375061f Content-Type: text/plain; charset="UTF-8" The generativity of record types is, I believe, one of the key prereqs for achieving a decidable type inference algorithm in the absence of any type annotations, in caml. That is, when you write a caml program and it fails to type-check, you can't make it type-check by adding "enough" type-annotations. For a programmer, this is critical -- when the compiler tells you that your program doesn't type-check, it means that your code is actually broken. Whereas in SML/NJ, you might need to add some more type-annotations. It was one of the things that convinced me to switch to caml, lo these many decades. On Tue, Jan 23, 2018 at 8:05 AM, Jeremy Yallop wrote: > > Yes: record definitions are indeed generative in OCaml, unlike in Standard > ML. > --f403043bb158a5337c056375061f Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
The generativity of record types is, I believe, one of the= key prereqs for achieving a decidable type inference algorithm in the abse= nce of any type annotations, in caml.=C2=A0 That is, when you write a caml = program and it fails to type-check, you can't make it type-check by add= ing "enough" type-annotations.=C2=A0 For a programmer, this is cr= itical -- when the compiler tells you that your program doesn't type-ch= eck, it means that your code is actually broken.=C2=A0 Whereas in SML/NJ, y= ou might need to add some more type-annotations.

It was = one of the things that convinced me to switch to caml, lo these many decade= s.

On Tue, Jan= 23, 2018 at 8:05 AM, Jeremy Yallop <yallop@gmail.com> wrote:=

Yes: record definitions are indeed generative in OCaml, unlike in St= andard ML.
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