go-arg
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alexflint
Description strings for subcommands
A descriptive message can be added at the top of the help text by implementing a Description function that returns a string.
./s-subcommands -h
this program does this and that
Usage: s-subcommands [--quiet] <command> [<args>]
Options:
--quiet, -q
--help, -h display this help and exit
Commands:
checkout
commit
push
Besides giving a descriptive message to the main program, please consider adding them for subcommands as well, like git:
clone Clone a repository into a new directory
init Create an empty Git repository or reinitialize an existing one
and use it for subcommand helps as well:
I.e., instead of:
./s-subcommands commit -h
this program does this and that
Usage: s-subcommands commit [--all] [--message MESSAGE]
Options:
--all, -a
--message MESSAGE, -m MESSAGE
Global options:
--quiet, -q
--help, -h display this help and exit
The first line better be
commit - Record changes to the repository
Well ok the reason for this is that subcommands are nil pointers when the help string for the parent command is being printed. I didn't want to assume that you could safely call Description() on a nil struct. I think most implementations of Description() just return a static string, or at least do not access the receiver struct, but still some users might be confused by having Description() invoked with a nil receiver.
The way to get the output you want, though will in involve repetition in your code, is to add a help tag to the subcommand like this:
var args struct {
Commit *commitCmd `arg:"subcommand" help:"Record changes to the repository"`
}
I'm still open to implementing this, just considering options carefully.
Yeah, sure that'd do as well -- simpler=better.
Just that, when running ./s-subcommands commit -h, the first line is still
this program does this and that
but I think the first line better be:
commit - Record changes to the repository