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Text File  |  1987-12-30  |  1.3 KB  |  60 lines
  1. "
  2.      Class Block.
  3.  
  4.      Note how whileTrue: and whileFalse: depend upon the parser
  5.      optimizing the loops into control flow, rather than message
  6.      passing.  If this were not the case, whileTrue: would have to
  7.      be implemented using recursion, as follows:
  8.  
  9.      whileTrue: aBlock
  10.           (self value) ifFalse: [^nil].
  11.           aBlock value.
  12.           ^ self whileTrue: aBlock
  13. "
  14. Class Block
  15. [
  16.      newProcess
  17.           ^ <NewProcess  self>
  18. |
  19.      newProcessWith: argumentArray
  20.           ^ <NewProcess  self argumentArray>
  21. |
  22.      fork
  23.           self newProcess resume.
  24.           ^ nil
  25. |
  26.      forkWith: argumentArray
  27.           (self newProcessWith: argumentArray) resume.
  28.           ^ nil
  29. |
  30.      whileTrue
  31.           ^ [self value ] whileTrue: []
  32. |
  33.      whileTrue: aBlock
  34.           ^ [ self value ] whileTrue: [ aBlock value ]
  35. |
  36.      whileFalse
  37.           ^ [ self value ] whileFalse: []
  38. |
  39.      whileFalse: aBlock
  40.           ^ [ self value ] whileFalse: [ aBlock value ]
  41. |
  42.      value
  43.           <BlockExecute  0>
  44. |
  45.      value: a
  46.           <BlockExecute  1>
  47. |
  48.      value: a value: b
  49.           <BlockExecute  2>
  50. |
  51.      value: a value: b value: c
  52.           <BlockExecute  3>
  53. |
  54.      value: a value: b value: c value: d
  55.           <BlockExecute  4>
  56. |
  57.      value: a value: b value: c value: d value: e
  58.           <BlockExecute  5>
  59. ]
  60.