File: Field.i3 Last Modified On Fri Jun 24 09:30:30 PDT 1994 By kalsow

INTERFACE Field;

IMPORT M3ID, Type, Value, Expr;

TYPE T <: Value.T;

TYPE
  Info = RECORD
    name   : M3ID.T;
    index  : INTEGER;  (* 0..nFields-1 *)
    offset : INTEGER;  (* bit offset from beginning of record *)
    type   : Type.T;
    dfault : Expr.T;
  END;

PROCEDURE New (READONLY info: Info): Value.T;

PROCEDURE SetOffset (field: Value.T;  newOffset: INTEGER);

PROCEDURE Is (v: Value.T): BOOLEAN;

Returns TRUE iff 'v' is a field

PROCEDURE Split (field: Value.T;  VAR info: Info);

PROCEDURE Compile (field: T);

compile, i.e. declare, the underlying type

PROCEDURE EmitDeclaration (field: Value.T);

emit the C struct member or bit-field for 'field'

PROCEDURE IsEqualList (va, vb: Value.T;  x: Type.Assumption;
                       types: BOOLEAN): BOOLEAN;

Returns TRUE if the two lists of values represented by va and vb have the same length and for each pair of values a and b, IsEqual(a, b, x, types) returns TRUE. Otherwise, returns FALSE.

PROCEDURE IsEqual (va, vb: Value.T;  x: Type.Assumption;  types: BOOLEAN): BOOLEAN;

If types is FALSE, only the surface syntax (name & field index) are checked. Otherwise, the field types and default values are checked too.

END Field.