Example From UVA ADEPTUVA Package Declaration

PACKAGE uva IS

TYPE Handshake IS (Removed, Acked, Released, Present);

TYPE Token_Fields IS (Status, Tag1, Tag2, Tag3, Index, Act_Time, Color);

TYPE Color_Type IS

ARRAY(Token_Fields RANGE Tag1 TO Act_Time) OF INTEGER;

TYPE Token IS

RECORD

Status : Handshake;

Color : Color_Type;

END RECORD;

TYPE Token_Vector IS ARRAY (Integer RANGE <> ) OF Token;

FUNCTION Protocol (Input : Token_Vector) RETURN Token;

SUBTYPE Token_Res IS Protocol Token;

CONSTANT Def_Colors : Color_Type := (OTHERS=ɬ);

CONSTANT Def_Source_Token : Token := (Released,Def_Colors);

CONSTANT Def_Sink_Token : Token := (Removed,Def_Colors);

-- Package declaration continued on next slide

UVa

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The package declaration required for this example is shown here. Several required data types and useful constants are declared. Note, for example, that the token type is a record that contains an enumerated type and an array of integers.

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