Unsettling dialyzer errors

[Josef Svenningsson]

On Sun, Feb 28, 2021 at 9:12 PM Nicolas Martyanoff <khaelin@REDACTED>
wrote:

> Josef Svenningsson <josef.svenningsson@REDACTED> writes:
>
> > On 2/28/21 11:39 AM, Josef Svenningsson wrote:
> > No, Gradualizer is not saying that foo/1 should take arguments of type
> > t1(). It's saying that the program calls f1/1 with a variable of type
> > t1()|t2() but the declared type of f1/1 only accepts arguments of t1().
> > Hence the error.
> > Gradualizer looks at the declared types of functions and will report an
> > error if there is an incompatibility, but it doesn't "expect" the types
> to
> > be anything.
> This is the behaviour I expect from a type checker. Too many times, I
> end up with errors about types that Dialyzer itself inferred,
> having to find out how they relate to the type specifications I
> provided.
>
> I'll try to run Gradualizer on my main codebase, it should be quite
> interesting.
>
> I'm glad to hear you're giving it a try. Given that you've used Dialyzer
in the past and it treats specs somewhat differently compared to
Gradualizer, be prepared to have to alter the specs somewhat. But I hope
that it should be relatively straightforward. Gradualizer is designed to be
a fairly conventional type system so if you have experience with those
before then I think you should feel at home. Let us know if anything trips
you up.

Cheers,

Josef
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