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修复练习3.6的错误 #58

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修复练习3.6的错误 #58

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50ca3c0
Update 6-rand.scm
DL-85 Apr 30, 2019
d193edc
修复练习3.6错误
DL-85 Apr 30, 2019
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2 changes: 0 additions & 2 deletions chp3/6.rst
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Original file line number Diff line number Diff line change
@@ -1,8 +1,6 @@
练习 3.6
==========

.. warning:: 本解法有错误，正等待修复中，具体请参考： http://sicp.readthedocs.org/en/latest/chp3/6.html#comment-770974238

这题使用了 3.1.1 和 3.1.2 小节的状态、消息传递和随机数等知识：

.. literalinclude:: code/6-rand.scm
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3 changes: 2 additions & 1 deletion chp3/code/6-rand.scm
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Expand Up @@ -6,7 +6,8 @@
(let ((state random-init))
(lambda (mode)
(cond ((eq? mode 'generate) ; 产生随机数
(random state))
(begin (set! state (rand-update state))
state))
((eq? mode 'reset) ; 返回一个过程
(lambda (new-value) ; 这个过程将 state 修改为新值 new-value
(set! state new-value)
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