commit e8ec36e6e91bab717edc73211f9e289d2e2d4764
author Todd Wang <toddw@google.com> Fri Oct 16 09:37:35 2015 -0700
committer Todd Wang <toddw@google.com> Fri Oct 16 09:37:35 2015 -0700
tree 5f5f68dc77479666cf648a7785c78f339228a867
parent 69794dd99076ce09aee024565df9640499d0deff

lib: Remove TODO comment regarding -metadata flag.

The intended usage of the -metadata flag is that whenever it is
set on the command-line, the program will dump metadata to stdout
and gracefully terminate.

Originally I had planned to implement this by making the Set
method return a metadata.ErrFlag error.  This way the caller of
FlagSet.Parse could check the error against metadata.ErrFlag, and
do whatever they liked.

However there was a bug in the flag package that ignored errors
returned by Set for boolean flags.  That's been fixed:
https://github.com/golang/go/commit/bc611a31a5b3003ba6c05d337093f9b83e898209

But there's still a catch.  The flag package wraps the errors
returned by Set with its own error.  That means the caller of
FlagSet.Parse cannot distinguish the error based on its type or
value.

So I'm giving up and getting rid of the TODO.  Calling os.Exit(0)
is ugly, but is fine for all practical purposes.

Change-Id: Id04d3b3d6564327156f9e6c5dbd9301598c161a7