Question

I use the Leiningen 2 REPL with Clojure 1.3.
I get an inconsistent behavior (or so I think) with meta data.

If this is as it should be, please explain. If not – where shall I file the bug?

This is how metadate should work, AFAIK.

main=> (def a ^:inited  [ 1 2 3])
main=> (meta a)
{:inited true}

And this is what I get when refering to an quoted empty sequence.

main=> (def a ^:inited  '() )
main=> (meta a)
nil

main=> (def a ^{:inited (System/currentTimeMillis)} '())
main=> (meta a)
nil

For an unquoted empty sequence, everything is fine. But, well, I get line numbers.

main=> (def a ^{:inited (System/currentTimeMillis)} ())
main=> (meta a)
{:inited 1339678437612, :line 1}

main=> (def a ^:inited  () )
main=> (meta a)
{:inited true, :line 1}

Here I don’t get line numbers:

main=> (def a ^:inited  [ 1 2 3])
main=> (meta a)
{:inited true}

main=> (def a ^{:inited (System/currentTimeMillis)} [1 2 3])
main=> (meta a)
{:inited 1339678534644}

Answer 1

The ' is a reader macro which expands to (quote ...). So you put the meta data on the list. Try this:

user=> (def a ' ^:inited [])
#'user/a
user=> (meta a)
{:tag :inited}
user=> (def a ^:inited '[])
#'user/a
user=> (meta a)
nil

Shameless self-promotion.