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137 :: ORM using macros

• exhu (orginal) [2013-03-21T20:56:18+01:00] view original

  Can anyone suggest nimrod's syntax features to assist in attaching metadata (for writing a macro) ?

  Can't find any way to attach declarative metadata to fields, dumpTree() fails for both of those 1) the comments are not part of the tree

  2. doesn't compile, because {.id.} or any other string is recognized as unknown pragma...

  
  # comments are ignored, so this way doesn't work
  
  dumpTree:
    type
          TMyDs = object
              ## used for inserting new entries and querrying.
              ## FIELD ORDER IS IMPORTANT!
              id: TEntityId # SQL=id
              name: string # SQL=name
              originalPath: string # SQL=original_path
              scanTime: TTime # SQL=scan_time
              rootId: TEntityId # SQL=root_id
  
  
  # here the compiler
  dumpTree:
    type
          TMyDs = object
              ## used for inserting new entries and querrying.
              ## FIELD ORDER IS IMPORTANT!
              id {.id.}: TEntityId # SQL=id
              name: string # SQL=name
              originalPath: string # SQL=original_path
              scanTime: TTime # SQL=scan_time
              rootId: TEntityId # SQL=root_id
  Run

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• Araq (orginal) [2013-03-23T08:47:28+01:00] view original

  For dumpTree to work, use a dummy {.pragma: id.} declaration. This is however only necessary for developing your macro, the macro should be immediate and remove the id pragma so that the semantic checking that happens after macro expansion doesn't see it. In other words:

  
  
  # only necessary for 'dumpTree' to work:
  {.pragma: id.}
  
  dumpTree:
    type
          TMyDs = object
              id {.id.}: TEntityId
  ...
  Run

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• exhu (orginal) [2013-03-24T15:48:29+01:00] view original

  I get

  
  testdsmacro.nim(50, 22) Error: invalid visibility: '*'
  Run

  for the following piece of code:

  
  dumpTree:
      type
          TDirEntryDesc* = tuple
              ## used for inserting new entries and querrying.
              ## FIELD ORDER IS IMPORTANT!
              id: TEntityId
              parentId: TEntityId
  Run

  So how can i declare a public type with a macro?

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• Araq (orginal) [2013-03-25T02:21:38+01:00] view original

  Use the new dumpTreeImm macro instead.

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• gradha (orginal) [2013-04-13T17:08:29+02:00] view original

  How's the ORM going? Is it good enough to use for quick CRUD for a basic website with jester?

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• exhu (orginal) [2013-04-14T02:08:48+02:00] view original

  I've been on a vacation far from internets and computers, and it was not ready when i left and is forgotten now. Anyway i'm not writing a general-purpose library, i write a module to suit my own project only, and plan to generalize interfaces after the project matures, so that db stuff can be generalized and extracted as an independent lib.

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