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1529 :: macros.getType

• EXetoC (orginal) [2015-08-13T12:42:06+02:00] view original

  Did someone say that the macro API is supposed to offer everything that the typeinfo module can do?

  Two things I haven't been able to figure out are:

  • How to determine unambiguously whether or not a symbol is referring to the int type for example.
  • How to get the size of a type referred to by a symbol.

  Is there anything that hasn't been implemented yet?

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• andrea (orginal) [2015-08-13T12:46:00+02:00] view original

  See this previous discussion

  In short:

  proc hasType(x: NimNode, t: static[string]): bool {. compileTime .} =
    sameType(x, bindSym(t))
  
  # then, inside a macro...
  if field.hasType("int"): # do something
  Run

  I am not sure how to get the type size, though. I think you can write your helper that recurse over the type and sums up the size of the components, starting from the sizes of ints and floats

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• EXetoC (orginal) [2015-08-13T12:51:36+02:00] view original

  That was easy. I might have everything I need then. thanks

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• EXetoC (orginal) [2015-08-13T19:04:18+02:00] view original

  it returns false if int for example is declared in the current scope too, but it's a start

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• Araq (orginal) [2015-08-13T20:48:44+02:00] view original

  Well since bindSym is evaluated in the current scope, where you have full control about its contents, there is nothing wrong. Also you can bindSym"system.int".

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