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2 Future Creation Tree

The creation tree shows a tree with a single node per future created by the program. This display can be particularly useful for programs which spawn futures in nested fashion (futures within futures). For any given future node, the children of that node represent futures which were created by that future (within the scope of its thunk). For all programs, the root of the tree is a special node representing the main computation thread (the runtime thread), and is denoted RTT.


(creation-tree-pict events    
  [#:x x    
  #:y y    
  #:width width    
  #:node-width node-width    
  #:height height    
  #:padding padding    
  #:zoom zoom])  pict?
  events : (listof indexed-future-event?)
  x : (or #f exact-nonnegative-integer?) = #f
  y : (or #f exact-nonnegative-integer?) = #f
  width : (or #f exact-nonnegative-integer?) = #f
  node-width : (or #f exact-nonnegative-integer?) = #f
  height : (or #f exact-nonnegative-integer?) = #f
  padding : (or #f exact-nonnegative-integer?) = #f
  zoom : exact-nonnegative-integer? = 1
Returns a pict showing the future creation tree for the trace in events. The optional arguments x, y, width, and height can be used to obtain a specific area (in pixels) of the creation tree image. The node-width argument specifies (in pixels) the diameter of each node. The padding argument specifies the minimum space vertically between each depth and horizontally between siblings. The zoom argument specifies the zoom factor for the tree image in the range 1-5, where 5 returns a 500% zoom.