anchor.diff:  
   TIP: It is possible to enabled profiling for a Gremlin Console session via `gremlin.sh -p`.
   
  +[[random-step]]
  +Random Step
  +~~~~~~~~~~~
  +
  +To randomly filter out a traverser, use `random()`-step (*filter*). The provided double argument biases the "coin toss."
  +
  +[source,groovy]
  +gremlin> g.V().random(0.5)
  +==>v[2]
  +==>v[3]
  +gremlin> g.V().random(0.0)
  +gremlin> g.V().random(1.0)
  +==>v[1]
  +==>v[2]
  +==>v[3]
  +==>v[4]
  +==>v[5]
  +==>v[6]
  +
   [[range-step]]
   Range Step
   ~~~~~~~~~~
  
positive.code: ==>v[1]
  ==>v[1]
  ==>v[1]
  
  [[select-step]]
  Select Step
  
negative.code: ==>[v[1], v[3], v[1]]
  ==>[v[1], v[2], v[1]]
  ==>[v[1], v[4], v[1]]
  
  [[dedup-step]]
  Dedup Step
  ~~~~~~~~~~
  
  With `dedup()`-step (*filter*), repeatedly seen objects are removed from the traversal stream. Note that if a traverser's bulk is greater than 1, then it is set to 1 before being emitted.
  
  [source,groovy]
  gremlin> g.V().value('lang')
  ==>java
  ==>java
  gremlin> g.V().value('lang').dedup()
  ==>java
  
  If a lambda is provided to `dedup()`, then the object is processed by the lambda prior to determining if it has been seen or not.
  
  [source,groovy]
  gremlin> g.V().value('name').map{[it.get(), it.get().length()]}
  ==>[marko, 5]
  ==>[vadas, 5]
  ==>[lop, 3]
  ==>[josh, 4]
  ==>[ripple, 6]
  ==>[peter, 5]
  gremlin> g.V().value('name').dedup{it.get().length()}
  ==>marko
  ==>lop
  ==>josh
  ==>ripple
  
  [[except-step]]
  Except Step
  ~~~~~~~~~~~
  
  The `except()`-step (*filter*) can be used to remove objects from the traversal stream. If `except()` is provided a string, then the excepting object is located at `traverser.sideEffects().get(label)`. If `except()` is provided a collection, then any object contained in that collection is filtered out. Please see the related <<retain-step,`retain()`-step>>.
  
  [source,groovy]
  gremlin> g.v(1).as('x').out('created').in('created')
  ==>v[1]
  ==>v[4]
  ==>v[6]
  gremlin> g.v(1).as('x').out('created').in('created').except('x') // co-developers
  ==>v[4]
  ==>v[6]
  gremlin> g.v(1).as('x').out('created').in('created').value('name')
  ==>marko
  ==>josh
  ==>peter
  gremlin> g.v(1).as('x').out('created').in('created').value('name').except(['marko','stephen'])
  ==>josh
  ==>peter
  
  [[fold-step]]
  Fold Step
  