title: How to handle masking conflicts in R package the right way?
body: <p>I wonder what the best way to handle masking conflicts the right way if the conflicting packages are not my own packages. Consider the following example. I work a lot with time series
  and typically function names like quarter, year etc. are used quite often. So if I load <code>tis</code> and <code>data.table</code> the functionality of R clearly depends on the sequence the packages are loaded. </p>
  
  <pre><code>library(tis)
  library(data.table)
  # this masks: between, month, quarter, year
  library(TSfame) # loads TSdbi
  con &lt;- TSconnect("somefame.db")
  # the following fails when data.table was loaded after tis
  ts1 &lt;- TSget("somekeyInYourDB",con)
  </code></pre>
  
  <p>and TSget from the <code>TSdbi</code> package does not work anymore. Do I need to fork the package and implement some <code>::</code> syntax? The example might be specific, but the question is pretty general. What would more experienced users do?</p>
  
  <p>EDIT: Probably I need to state this more clearly. The problem is that I don't have a chance to call the function explicitly because TSget is calling the function that should be called explicitly and assumes that there's only tis.</p>
  
  <p>EDIT2, adding the call stack as requested by Richie Cotton:</p>
  
  <pre><code> Tracing year(actualStart) on entry 
   [[1]]
   TSget("kofbauindikator_total", con)
  
   [[2]]
    TSget("kofbauindikator_total", con)
  
   [[3]]
   .local(serIDs, con, ...)
  
   [[4]]
    getfame(serIDs[i], dbname[i], save = FALSE, envir = parent.frame(), 
    start = NULL, end = NULL, getDoc = FALSE)
  
    [[5]]
    year(actualStart)
  
     [[6]]
    .doTrace((function () 
    print(sys.calls()))(), "on entry")
  
   [[7]]
   eval.parent(exprObj)
  
   [[8]]
   eval(expr, p)
  
   [[9]]
   eval(expr, envir, enclos)
  
   [[10]]
   (function () 
    print(sys.calls()))()
  
   Error in as.POSIXlt.default(x) : 
      do not know how to convert 'x' to class “POSIXlt”
  </code></pre>