author | Christian Urban <christian dot urban at kcl dot ac dot uk> |
Fri, 15 Jul 2016 10:54:09 +0100 | |
changeset 406 | 0a42d73e795b |
parent 399 | 5c1fbb39c93e |
child 412 | 1cef3924f7a2 |
permissions | -rw-r--r-- |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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def simp(r: Rexp): Rexp = r match { |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case ALT(r1, r2) => { |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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(simp(r1), simp(r2)) match { |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case (ZERO, r2s) => r2s |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case (r1s, ZERO) => r1s |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case (r1s, r2s) => if (r1s == r2s) r1s else ALT(r1s, r2s) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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} |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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} |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case SEQ(r1, r2) => { |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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(simp(r1), simp(r2)) match { |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case (ZERO, _) => ZERO |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case (_, ZERO) => ZERO |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case (ONE, r2s) => r2s |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case (r1s, ONE) => r1s |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case (r1s, r2s) => SEQ(r1s, r2s) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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} |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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} |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case NTIMES(r, n) => NTIMES(simp(r), n) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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case r => r |
7 | 20 |
} |
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||
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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def ders (s: List[Char], r: Rexp) : Rexp = s match { |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case Nil => r |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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case c::s => ders(s, simp(der(c, r))) (*@\label{simpline}@*) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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} |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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26 |