Improve error message for when we pass wrong arguments to a function

[ryuukk]

I think it looks better!

[dlang-bot]

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[ljmf00]

You need to change the tests that are making this fail accordingly.

[ibuclaw]

1. Can we really not have one error == one line here?
2. Avoid mixing tabs and spaces.
3. Do we use %*s as a format specifier in other errors? (Meaning, has it been vetted as a portable format to use).

[ljmf00]

I guess you prepended a space by mistake in both lines

[ryuukk]

You need to change the tests that are making this fail accordingly.

i'll look into it, thanks

1. Can we really not have one error == one line here?

It wasn't really readable before as a one line

2. Avoid mixing tabs and spaces.

I'll fix that

3. Do we use %*s as a format specifier in other errors? (Meaning, has it been vetted as a portable format to use).

I have no idea..

[dkorpel]

You need to change the tests that are making this fail accordingly.

i'll look into it, thanks

You can use AUTO_UPDATE=1 ./run.d fail, see:
https://github.com/dlang/dmd/tree/master/test#quick-guide

[ibuclaw]

1. Can we really not have one error == one line here?

It wasn't really readable before as a one line

I mean, you can break up an error into multiple lines using errorSupplemental for subsequent messages.

[nordlow]

Awesome that you're looking into improving diagnostic!

Could we somehow utilize alignment to make it easier to spot which parameter (index) that is fed the wrong parameter?

[nordlow]

I have another request which might belong in a separate PR, namely:

The code snippet

    void f(T)(int x) {}
    unittest { f(42); }

currently erroring as

    template `missing_template_param.f` cannot deduce function from argument types `!()(int)`
    Candidate is: `f(T)(int x)`

could also include a errorSupplemental like

    Candidate `f(T)(int x)` is missing a/its/its (single)/(the first) template parameter `T`

.

[ryuukk]

You need to change the tests that are making this fail accordingly.

i'll look into it, thanks

You can use AUTO_UPDATE=1 ./run.d fail, see: https://github.com/dlang/dmd/tree/master/test#quick-guide

thanks!

1. Can we really not have one error == one line here?

It wasn't really readable before as a one line

I mean, you can break up an error into multiple lines using errorSupplemental for subsequent messages.

i will do that!

@nordlow

that was initially the goal, to put arrows to display wich one is the problem, or maybe put some color, but i'm not familiar with the code base and i got distracted by my wasm project, that's something definitely worth trying, i will try to find some time and finish this little side project of mine!

[RazvanN7]

@ryuukk any progress on this?

[ryuukk]

@RazvanN7 i am still busy working on my WASM project, also some people raised some interesting point on IRC that i need to take into consideration

So i want to improve it further

[moon-chilled]

%*s

%*s is specified in c89. It is not used as such elsewhere in dmd, but %.*s is used; so the feature is still required.