feat: add format specifiers for `api.Println` or implement `api.Printf`

[George551556]

To be precise, I think you can add a func like api.Printf("this is my var %fv. ", circuit.x), and hope it have the same performance with fmt.Printf()

func (circuit *Circuit) Define(api frontend.API) error{
    api.Printf("this is my var %fv. ", circuit.x)
}
go
cmd output: this is my var 2

[ivokub]

It could be useful - I think we could have different formatting options:

• hex
• int
• small integer - if value is small when considered as a negative, then print that instead
• coefficient ID
• variable ID

[zliucd]

@ivokub In addition to api.Println(), it's possible to provide a new API api.Fmt() that feeds the printing content to a string?

[ivokub]

It is possible, but we currently don't have it on the roadmap. I think it could be a suitable task for external contribution though.