I just wrote my own trivial macro for that, which I use in conjunction with my little https://github.com/ScottPJones/StringUtils.jl (unregistered) package to get easily formatted debugging output.
const global debug = [false]
:( debug && println($(esc(str))) )
and in the code I have things like:
@deb(u"These are floats: \%8.2f(1.2345), \%8.3f(9.8765)")
and get nicely formatted output like:
These are floats: 1.23, 9.877
Then to enable debugging output of that module, I simple do:
Foo.debug = true.