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1293 :: First example of rewrite rule

• andrea (orginal) [2015-06-04T16:41:43+02:00] view original

  I am trying to figure out how to write a rewrite rule. My first example would be

  template helloRewrite{`*`(`*`(a, b), c)}(a, b, c: int): int =
    echo "huuu"
    41
  
  echo((3 * 5) * 2)
  echo(3 * 5 * 2)
  Run

  Apparently, none of those two example matches. What am I doing wrong?

  PS I know I can match nested binary expressions with the * operator, but I actually need a fixed number of parameters. My aim would be to rewrite operations such as this to a single BLAS function call.

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• def (orginal) [2015-06-04T17:07:26+02:00] view original

  This already gets calculated by Nim's VM at compile time. Check the resulting C code and you'll find:

  STRING_LITERAL(TMP5, "30", 2);
  printf("%s\012", ((NimStringDesc*) &TMP5)? (((NimStringDesc*) &TMP5))->data:"nil");
  printf("%s\012", ((NimStringDesc*) &TMP5)? (((NimStringDesc*) &TMP5))->data:"nil");
  Run

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• andrea (orginal) [2015-06-04T18:10:31+02:00] view original

  Thank you - I tried this with values known at runtime and in fact it works... Now I have to figure out why it is not working in may actual use case :-/

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