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alexray19 Group Title

In Racket, say you're given this: '( 'blah 'foo a) and a is not defined. If you're iterating through the list, how can you test whether the element is a 'symbol (like blah or foo) or if it's an unbound variable, like a?

  • 7 months ago
  • 7 months ago

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  1. alexray19 Group Title
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    What I'm trying to do is write a list of differentiation rules that uses patterns. So an input matching the pattern '( ('ddx ('plus u v))), where u an v are pattern variables, should be translated to '( ('plus ('ddx u) ('ddx v))). But my "translator" will need to know that 'plus is just a symbol, while u and v are pattern variables.

    • 7 months ago
  2. wio Group Title
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    What about `(symbol?` ` )`

    • 7 months ago
  3. wio Group Title
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    The pattern variables won't be symbols, correct?

    • 7 months ago
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spraguer (Moderator)
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