Re: [Gm2] [Exporting and Importing amongst inner modules

[john o goyo]

On 3 Jun 2014, at 05:51, Gaius Mulley wrote (in part):

> john o goyo <address@hidden> writes:
>
> > Thie following problem occurs with gm2-4.1.2 (given that I am
> > currently stuck building mpfr).  I cannot remember if this was
> > reported before and I could not find anything on the mailing list.
>
> Hi John,
>
> thanks for the report - I cannot remember this being reported before.
> I think there are some problems with the test code though:
>
>
> > Symbols exported from one inner module are not seen within a second
> > inner module.  Example code follows.
> >
> >
> > MODULE InnerModules;
> >  (*-------------------------*)
> >  MODULE FirstInner;
> >
> >  EXPORT One;  (* Not seen by gm2 *)
> >
> >  PROCEDURE One() :CARDINAL;
> >  BEGIN
> >    RETURN 1;
> >  END One;
> >
> >  END FirstInner;
> >
> >  (*-------------------------*)
> >  MODULE SecondInner;
> >
> >  FROM FirstInner IMPORT One; (* Will not compile *)
>
> I think this should be:
>
>    IMPORT One;
>
> as the 'FROM' statement looks up modules from the global universe.

Interesting... this was a distillation from the file MCP1IO.mod of the  
M2M (ETH) compiler.  (The same file is in the ULM distribution.)

Here is the truncated file showing the imports.

(****************************************
*                                       *
*     MODULA-2 Multi-Pass Compiler      *
*     ****************************      *
*                                       *
*     Implementation for Lilith         *
*                                       *
*                                       *
*     MCP1IO:                           *
*                                       *
*     input / output handling in Pass 1 *
*                                       *
*     Version C18 of 11.03.82           *
*                                       *
*     Institut fuer Informatik          *
*     ETH-Zuerich                       *
*     CH-8092 Zuerich                   *
*                                       *
****************************************)

(* changed to handle tabs 9.9.83 *)

IMPLEMENTATION MODULE MCP1IO;      (* LG *)
  (*...*)

  MODULE OutputSystem;
  (*...*)
    EXPORT
      PutS, PutSy, PutSyVal, PutIdent, Error,
      InitSave, StopSave, RestartSave, ReleaseSys,
      InitOutput, TermOutput;
  (*...*)
  END OutputSystem;

 MODULE IdentSystem;
  (*...*)
    FROM OutputSystem IMPORT Error;
  (*...*)
  END IdentSystem;

  MODULE StringSystem;
  (*...*)
    FROM OutputSystem IMPORT Error;
  (*...*)
  END StringSystem;

  MODULE SymFileInput;
  (*...*)
    FROM OutputSystem IMPORT PutS, StopSave, RestartSave, Error;
    FROM IdentSystem IMPORT InIdTab, OutIdTab, EnterId;
    FROM StringSystem IMPORT PutStrCh, InitString, TermString;
  (*...*)
  END SymFileInput;

  MODULE Scanner;
  (*...*)
    FROM OutputSystem IMPORT PutS, PutSyVal, Error;
    FROM IdentSystem IMPORT InIdTab, EnterId;
    FROM StringSystem IMPORT InitString, PutStrCh, TermString;
  (*...*)
  END Scanner;

  (*...*)
END MCP1IO.


john