Flags in FDB from 1.18¶

I posted recently that FDB 1.18 has been released and that one of the changes in there was that my custom flags library for handling command line options (switches; flags; things like -a) has been replaced with the standard optparse library. (Thanks again, Yevgev (@xa4a_)

When I wrote that post, I hadn’t fully appreciated that this had subtly changed the behaviour of command line arguments, and in doing so invalidated some of the examples I posted.

Most people will almost certainly prefer the new behaviour (or at least, will probadbly find it more familiar), but since its different and inconsistent with previous published examples, I thought I’d better document it.

The main changes are as follows:

• Single-letter options may no longer be conflated, i.e.

  USE   fdb tag -v -a DADGAD rating=10
  NOT   fdb tag -av DADGAD rating=10

  to specify that you want to set a rating of 10 on the object whose object whose about tag is DADGAD

• -q, -a and -i now take the argument immediately following as the query, about-tag or ID, rather than using the first argument not tied to an option. So

  USE   fdb tag -v -a DADGAD rating=10
        fdb tag -sand -i edfaaf70-b9b5-42f1-ad4c-30601b70a2ac rating=10
        fdb tag -v -sand -q "has njr/rating" rating=10
  USE   fdb tag -a -v DADGAD rating=10
        fdb tag -i -sand edfaaf70-b9b5-42f1-ad4c-30601b70a2ac rating=10
        fdb tag -v -q -sand "has njr/rating" rating=10

• options may now appear anywhere in the command

  USE  fdb tag -i -sand edfaaf70-b9b5-42f1-ad4c-30601b70a2ac rating=10
  OR   fdb tag -i edfaaf70-b9b5-42f1-ad4c-30601b70a2ac rating=10 -sand
  OR   fdb -i edfaaf70-b9b5-42f1-ad4c-30601b70a2ac tag rating=10 -sand

• there are now long versions with -- available to go with the short (single-letter) form for each action. (Personally, I hate --, but I lost that battle years ago.) Specifically, you can use

  --about ABOUT, -a ABOUT  to specify an about tag of ABOUT
  --id ID, -i ID           to specify an id of ID
  --query QUERY, -q QUERY  to specify a query of QUERY
  --timeout N, -T N        to specify an Http timeout of N
  --sandbox, -s            to specify use of the sandbox
  --verbose, -v            to increase verbosity
  --debug, -D              for debug mode