Positional arguments about go-flags

[jessevdk]

Ok, I've finally come around to implementing this. It works a bit differently than suggested though. You can now specify a tag positional-args:"true" on a struct field which then makes the struct members being parsed as the positional arguments, in order. A slice field automatically gets all the rest arguments appended. See also the example in the docs for how to use this.

[jessevdk]

Not really, it seems too trivial. You can just do:

LocalPath, RemoteUrl, Tags := args[0], args[1], args[2:]

[tobstarr]

Yes, you can but e.g. args[2:] breaks badly if your slice is not long enough. So you would need some (boilerplate) checking if the non-flag arguments have a specific length. This could be done in the same way it is done with the flags (validations, type conversions, min/max for slice types etc).

But I was just curious.

[jessevdk]

Ok sure. Personally, I never really write applications with have a specific order of positional arguments as it always seems to be hard to remember their order, and thus I much prefer flags. That said, I can see how it's a matter of opinion. Let's say, patches are welcome :)

[tobstarr]

Normally I also prefer flagged arguments. There are some cases where positional (especially of type slice) make sense. I am looking at the whole familiy of ec2 cli tools (like ec2-describe-instances id [id...], ec2-terminate-instances id [id...], etc)

[jessevdk]

Well, args is also a slice! ec2-describe-instances doesn't seem like a particularly good example of why you would need more support for positional arguments.