What to do with 3 or more dashes

[joesepi]

See: #1 (comment)

See also near bottom of FAQs, design doc says:

Is ---foo the same as --foo?

• no
• the first flag would be parsed as '-foo'
• the second flag would be parsed as 'foo'

https://github.com/pkgjs/parseargs#faqs

[ljharb]

I would expect ---foo to be the flag "-foo", or an error - ie, the third dash shouldn't change how things are parsed.

[joesepi]

If we want to avoid throwing errors, should we simply warn or info on such a case where more than 2 dashes are used?

[ljharb]

Do we want that?

[darcyclarke]

@joesepi I don't think we want that & this question seems to have now been asked/answered in the FAQs section (ref. https://github.com/pkgjs/parseargs#faqs), re.

• Is ---foo the same as --foo?
  • no
  • the first flag would be parsed as '-foo'
  • the second flag would be parsed as 'foo'

The idea is that we keep a limited set of assumptions about names & values (ie. - is the prefix for shorthands & -- is the prefix for a flag... that's about it... no other validation). Notably, and something we should probably document, is that you can't ever make an alias/shorthand of "-" (as -- is a known/special identifier). Based on the current design though, we would interpret --- as if "-" is a flag name (ex. { args: { "-": true } ... } ~ which might be odd but is at least codified).

Throwing an error or even warning when we see --- would mean we're assuming the input is incorrect. I think, as a rule, we should always successfully parse all input without warning/error. Special cases/exception handling can be left to tooling authors that want to build off of this more primitive implementation.

Ex. of a simple two-liner someone could use to handle/warn of cases where --- is found...

// cli.js ---foo
const { parseArgs } = require('util')
const { args } = parseArgs()

// check for dashes & warn
const errs = Object.keys(args).filter(name => name.startsWith('-'))
if (errs.length) console.error(`Arguments passed beginning with dashes`) // ! Arguments passed beginning with dashes

[shadowspawn]

Closed by #21