@system: test macro calls without parentheses

[ueliwechsler]

Complete an element of checklist in #133.

See here , the solution is trivial 🙈

The syntax needs to be

@system x' = Ax + Bu  x∈X u∈U

without the commas.

I added the corresponding tests

[schillic]

I do not like this syntax.

[ueliwechsler]

I do not like this syntax.

Leaving out the commas?

[schillic]

Yes, this is not how you write a system definition on paper. I am fine with having this as an option of course. It works already, we can actually not avoid it, and I guess there is no way that , works without using (·) because this is how Julia parses expressions.
But I suggest to use the syntax @system(x' = Ax + Bu, x∈X, u∈U) rather than @system x' = Ax + Bu x∈X u∈U when showcasing.

[blegat]

I agree with @schillic, this is consistent with
http://www.juliaopt.org/JuMP.jl/v0.20.0/style/#JuMP-macro-syntax-1

[mforets]

See here , the solution is trivial see_no_evil

It is fun that we didn't realize this earlier :)

this is consistent with http://www.juliaopt.org/JuMP.jl/v0.20.0/style/#JuMP-macro-syntax-1

I agree as well that in @system the commas make it easier to parse the expression (for humans). On the other hand this behavior is already available, so i think it is a good idea to add the test proposed in this PR.