Re: Is this legal ?

[ftpbox!mothost!motcid!bachww@uunet.uu.net (Bud Bach)]

pelakh@convex.com (Boris Pelakh) writes:

> Blah, Blah, Blah...

>procedure BROKE is
>   type VAR_LINE(LENGTH : INTEGER := 10) is
>      record
>             IMAGE : STRING(1..LENGTH);
>      end record;
>   NULL_LINE : VAR_LINE;
>begin
>    null;
>end BROKE;

This is sort of a FAQ.

It has been fairly common for implementations to allocate the maximum
possible space in this situation.

Is it possible that you could constrain the length to something smaller
than "Integer"?

    procedure Common_Problem is

      subtype Reasonable_Length is Integer range 1..255;

      type Var_Line (Length : Reasonable_Length := 10) is
	record
	  Image : String (1 .. Length);
	end record;

    begin
      null;
    end Common_Problem;

Of course, knowing that the compiler will allocate "Reasonable_Length"
characters for each object of type "Var_Line", you might want to choose a
different representation.  Representations for strings always seem highly
application dependent.  There has been some recent discussion about string
representations in comp.compilers that you may want to reference.

Good luck,  -- Bud



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