--usage

usage explain ​

Explain what a command line binds to

Prints a row per argv token saying what it became, then the values that came from somewhere other than argv, then anything that went wrong. Exits 0 even when the explained command line does not parse: the report succeeded, and that is the case worth a report.

Arguments ​

[ARGV]… ​

The command line to explain, starting with the program name

usage's own flags come before it, and flag parsing ends at the program name, so both explain -f f.kdl mycli --env=prod and explain -f f.kdl -- mycli --env=prod work. Separate with -- when the explained line carries its own: the first -- is still usage's separator, so explain -f f.kdl mycli a -- b loses one.

Flags ​

-f --file <FILE> ​

A usage spec file or script with a usage shebang, use "-" to read from stdin

-s --spec <SPEC> ​

Raw string spec input

--format <FORMAT> ​

Output format

Choices:

  • text
  • json

Default: text

--view <VIEW> ​

A spec-declared executable view to explain

-e --env… <ENV> ​

Environment to explain against, as KEY=VALUE, repeatable

Given at all, these are the whole environment: an explanation pasted into a bug report has to mean the same thing on the machine that reads it. Omitted, the process environment is used, which is what an execution would see.

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