
<<SaffronPGOperationsImpl.Mesa>>
    <<Copyright Ó 1988 by Xerox Corporation.  All rights reserved.>>
    <<James Rauen, June 13, 1988 11:39:42 am PDT>>
    <<Last edited by: James Rauen June 15, 1988 12:52:27 pm PDT>>
    <<>>
    <<Implementation of operations related to Program Graphs>>
    <<>>
    DIRECTORY
        Convert USING [RopeFromInt],
        IO USING [int, PutF, STREAM],
        MessageWindow USING [Append, Blink],
        Rope USING [Concat, ROPE],
        SaffronPGDeclsDef USING [],
        SaffronPGOperations USING [],
        SaffronPGPrivateTypes USING [ProgramGraphNode, ProgramGraphNodeBody, EvaluatedExpressionNode, EvaluatedExpressionNodeBody];

    SaffronPGOperationsImpl: CEDAR PROGRAM 
        IMPORTS IO, MessageWindow, Rope, Convert
        EXPORTS SaffronPGDeclsDef, SaffronPGOperations ~ BEGIN

        ProgramGraphNode: TYPE ~ REF ProgramGraphNodeBody;
        ProgramGraphNodeBody: PUBLIC TYPE ~ SaffronPGPrivateTypes.ProgramGraphNodeBody;

    MakeBogusPGN: PUBLIC PROC [] RETURNS [ProgramGraphNode] ~ BEGIN
    foo: ProgramGraphNode _ NEW[ProgramGraphNodeBody];
    <<MessageWindow.Blink[];>>
    <<MessageWindow.Append["Making a bogus program graph node.", TRUE];>>
    RETURN[foo];
    END;

    MakeSemiBogusPGN: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [ProgramGraphNode] ~ BEGIN
    foo: ProgramGraphNode _ NEW[ProgramGraphNodeBody];
    foo.operation _ IntegerEvExpVal[e];
    <<MessageWindow.Blink[];>>
    <<MessageWindow.Append["Making a semibogus program graph node.", TRUE];>>
    RETURN[foo];
    END;

    PrintProgramGraph: PUBLIC PROC [stream: IO.STREAM, pg: ProgramGraphNode] RETURNS [BOOLEAN] ~ BEGIN
    IO.PutF[stream, "The computed value is %g\n", IO.int[pg.operation]];
    RETURN[TRUE];
    END;

    NewPrintProgramGraph: PUBLIC PROC [stream: IO.STREAM, pg: ProgramGraphNode] ~ BEGIN
    IO.PutF[stream, "The computed value is %g\n", IO.int[pg.operation]];
    END;


        EvaluatedExpressionNode: TYPE ~ SaffronPGPrivateTypes.EvaluatedExpressionNode;
        EvaluatedExpressionNodeBody: PUBLIC TYPE ~ SaffronPGPrivateTypes.EvaluatedExpressionNodeBody;

    MakeIntegerEvExp: PUBLIC PROC [i: INT] RETURNS [EvaluatedExpressionNode] ~ {
    MessageWindow.Blink[];
    MessageWindow.Append[Rope.Concat["Evaluated value = ", Convert.RopeFromInt[i]], TRUE];
    RETURN[NEW[EvaluatedExpressionNodeBody _ [integer[i]]]];
    };

    MakeRealEvExp: PUBLIC PROC [r: REAL] RETURNS [EvaluatedExpressionNode] ~ {
    RETURN[NEW[EvaluatedExpressionNodeBody _ [real[r]]]];
    };

    MakeBooleanEvExp: PUBLIC PROC [b: BOOLEAN] RETURNS [EvaluatedExpressionNode] ~ {
    RETURN[NEW[EvaluatedExpressionNodeBody _ [boolean[b]]]];
    };

    MakeRopeEvExp: PUBLIC PROC [r: Rope.ROPE] RETURNS [EvaluatedExpressionNode] ~ {
    RETURN[NEW[EvaluatedExpressionNodeBody _ [rope[r]]]];
    };

    MakeComputedEvExp: PUBLIC PROC [code: ProgramGraphNode] RETURNS [EvaluatedExpressionNode] ~ {
    RETURN[NEW[EvaluatedExpressionNodeBody _ [computed[code]]]];
    };

    IsIntegerEvExp: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [BOOLEAN] ~ {
    RETURN[e.type = integer];
    };

    IsRealEvExp: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [BOOLEAN] ~ {
    RETURN[e.type = real];
    };

    IsBooleanEvExp: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [BOOLEAN] ~ {
    RETURN[e.type = boolean];
    };

    IsRopeEvExp: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [BOOLEAN] ~ {
    RETURN[e.type = rope];
    };

    IsComputedEvExp: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [BOOLEAN] ~ {
    RETURN[e.type = computed];
    };

    EvExpTypeError: ERROR = CODE;

    IntegerEvExpVal: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [INT] ~ {
    WITH e SELECT FROM
    i: REF integer EvaluatedExpressionNodeBody => RETURN[i.value];
    ENDCASE;
    ERROR EvExpTypeError;
    };

    RealEvExpVal: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [REAL] ~ {
    WITH e SELECT FROM
    i: REF real EvaluatedExpressionNodeBody => RETURN[i.value];
    ENDCASE;
    ERROR EvExpTypeError;
    };

    BooleanEvExpVal: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [BOOLEAN] ~ {
    WITH e SELECT FROM
    i: REF boolean EvaluatedExpressionNodeBody => RETURN[i.value];
    ENDCASE;
    ERROR EvExpTypeError;
    };

    RopeEvExpVal: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [Rope.ROPE] ~ {
    WITH e SELECT FROM
    i: REF rope EvaluatedExpressionNodeBody => RETURN[i.value];
    ENDCASE;
    ERROR EvExpTypeError;
    };

    ComputedEvExpVal: PUBLIC PROC [e: EvaluatedExpressionNode] RETURNS [ProgramGraphNode] ~ {
    WITH e SELECT FROM
    i: REF computed EvaluatedExpressionNodeBody => RETURN[i.code];
    ENDCASE;
    ERROR EvExpTypeError;
    };

    DoTargetMachineOp: PUBLIC PROC [op: ATOM, lhs, rhs: EvaluatedExpressionNode] RETURNS [res: EvaluatedExpressionNode] ~ BEGIN
    SELECT op FROM
    $add    =>    res _ MakeIntegerEvExp[IntegerEvExpVal[lhs] + IntegerEvExpVal[rhs]]
    ENDCASE;
    END;


    END.


    <<>>