anchor.diff:  ==== Collection comprehension vs. `map` and `filter`
   
   Collection comprehension is actually quite similar to using `map` and `filter`
  -HOF on a collection. Indeed, a comprehension such as:
  +higher-order function on a collection. Indeed, a comprehension such as:
   [source,golo]
   ----
   list[f(x) foreach x in aList when pred(x)]
  
positive.code: aList: filter(^pred): map(^f)
  ----
  
  Thus, should you use collection comprehension or HOF? Despite some
  implementation differences, it's above all a matter of taste. Some people
  consider comprehension more readable, since it is more similar to the
  mathematical 
  
negative.code: let sums = [ a + b foreach a, b in couples ]
  ----
  
  Maps can also be created, provided the given expression is either a pair tuple or
  a instance of `Map.Entry` (you can use the predefined `mapEntry(key, value)`
  function to create such objects). For instance:
  [source,golo]
  