Add --no-headers option to rename

[jqnatividad]

Done in #97.

See below for more details...

[tmtmtmtm]

It would be useful if qsv rename could take a --no-headers argument, as a way to add column names to a CSV that doesn't currently have them. Or is there another way to do this?

[tmtmtmtm]

@jqnatividad Oh, that's an interesting approach. Is it possible to feed qsv cat that column list directly, though, or does this require first creating (and then later deleting) an intermediate file for the headers? If it's only the latter, that seems quite a bit clunkier than, for example, adding them in with sed.

[jqnatividad]

@tmtmtmtm yes. It does require creating an intermediate file for the headers:

qsv cat rows headers.csv headerless.csv --no-headers > withheaders.csv

Actually, you don't even need qsv to do this, and just use cat:

cat headers.csv headerless.csv > withheaders.csv

So many ways to skin the "cat" 😉,

And that's the beauty of a composable CLI - you can mix & match it with other CLI tools like sed, cat, curl, jq, etc. It really depends on your use case and what tools you have access to and familiar with.

For example, for somebody who is creating a data pipeline that receives a headerless csv from a data feed on a regular basis, the cat approach is cleaner than using sed.

Regardless, if you have a specific use case and a corresponding recipe that uses qsv in some way, please do add it to the Cookbook!

[tmtmtmtm]

@jqnatividad I'm trying to avoid needing to create (and remember to delete again) temporary files. I certainly can use other commands to do this, but one of the reasons I've switched from xsv to qsv is precisely because I can do now lots of other things directly that I was previously going out to other commands for. qsv rename is so much nicer for the cases where the data already has a header row, so I was hoping it would be easy to extend that to also work in the cases where it doesn't, especially as there's already a --no-headers option to lots of the other subcommands, that seems like it would also work perfectly here.

[jqnatividad]

The same reason I created the qsv fork, as I saw so many pending PRs that I needed myself and "scratched the itch."

Anyways, I see your point regarding --no-headers, and I do want to make qsv as logical, consistent and symmetric as possible, so I'll add it to rename.

[jqnatividad]

Done. See #97