author | Christian Urban <christian dot urban at kcl dot ac dot uk> |
Sat, 31 Oct 2015 11:37:55 +0000 | |
changeset 364 | 50ce3667c190 |
parent 261 | 24531cfaa36a |
child 399 | 5c1fbb39c93e |
permissions | -rw-r--r-- |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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def OPT(r: Rexp) = ALT(r, EMPTY) |
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24531cfaa36a
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
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def NTIMES(r: Rexp, n: Int) : Rexp = n match { |
24531cfaa36a
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
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case 0 => EMPTY |
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
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case 1 => r |
24531cfaa36a
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
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case n => SEQ(r, NTIMES(r, n - 1)) |
24531cfaa36a
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
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} |
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
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|
8 |