let's use Expect in all atoms

[yegor256]

Currently, we use Expect class just in a few atoms, where we want to have a detailed error reporting in case of user errors. Let's use it in all atoms.

[asmirnov-backend]

@yegor256 Should Expect be used for checking Attr.RHO?
For examlpe, transform this

new Dataized(this.take(Attr.RHO)).asNumber()

to this

Expect.at(this, Attr.RHO)
      .that(phi -> new Dataized(phi).asNumber())
      .otherwise("Attr.RHO must be a number for 'EOnumber'")
      .it();

[yegor256]

@asmirnov-backend yes, definitely, this will be helpful

[asmirnov-backend]

While using Expect some code duplicates appear, for example, next piece of code used in EOnumber$EOdiv, EOnumber$EOgt, EOnumber$EOplus, EOnumber$EOtimes (Ref: #3789)

Expect.at(this, Attr.RHO)
    .that(phi -> new Dataized(phi).asNumber())
    .otherwise("must be a number")
    .it();

Perhaps it would be useful to have a more clever Dataized with Expect class.

public class DataizableExpect {

    private final Expect<Phi> expect;

    public DataizableExpect(final Expect<Phi> expect) {
        this.expect = expect;
    }

    public Double asDouble() {
        return this.expect
            .that(phi -> new Dataized(phi).asNumber())
            .otherwise("must be a number")
            .it();
    }

    public Integer asPositiveInt() {
        return this.expect
            .that(phi -> new Dataized(phi).asNumber())
            .otherwise("must be a number")
            .must(number -> number % 1 == 0)
            .that(Double::intValue)
            .otherwise("must be an integer")
            .must(integer -> integer >= 0)
            .otherwise("must be a positive integer")
            .it();
    }

}

The code that uses this class would look something like this:

new DataizableExpect(Expect.at(this, Attr.RHO)).asDouble()

@yegor256 What do you think?

[yegor256]

@asmirnov-backend maybe we can make inner classes:

new Expect.Number(Expect.at(this, Attr.RHO)).it();
new Expect.Integer(Expect.at(this, Attr.RHO)).it();
new Expect.Whole(Expect.at(this, Attr.RHO)).it(); // greater or equal to zero

WDYT?

[asmirnov-backend]

@yegor256 Nice idea, thanks