Length of the queue

[fogfish]

A function -spec esq:length(_) -> integer() is a nice feature. There are no rocket science to make it for in-memory queue. However, the file queue requires persistency of counter that would cause extra unnecessary disk I/O.

Alternative option `-spec esq:empty(_) -> true | false.'

[fogfish]

@silviucpp any thought ?

[silviucpp]

Your alternative is good enough :)