
    <<ParseTreePrinting.Mesa>>
        <<Copyright © 1986 by Xerox Corporation.  All rights reserved.>>
        <<Spreitzer, February 22, 1986 7:08:38 pm PST>>

    DIRECTORY Convert, EDIFfing, IO, Rope, StructuredStreams, UnparserBuffer;

    ParseTreePrinting: CEDAR PROGRAM
        IMPORTS Convert, IO, StructuredStreams, UnparserBuffer

        = {OPEN EDIFfing, SS: StructuredStreams, UB: UnparserBuffer;

        LORA: TYPE = LIST OF REF ANY;
        ROPE: TYPE = Rope.ROPE;

        breakLast: BOOL _ TRUE;
        lastOffset: INT _ 0;

        PrettyPrintParseTree: PROC [to: IO.STREAM, pt: ParseTree] = {
            WITH pt SELECT FROM
                x: REF ParseTreePrivate.string => {
                    to.PutRope[Convert.RopeFromRope[x.s]];
                    };
                x: REF ParseTreePrivate.integer => {
                    to.PutF["%g", [integer[x.i]]];
                    };
                x: REF ParseTreePrivate.identifier => {
                    to.PutF["%g", [atom[x.id]]];
                    };
                form: REF ParseTreePrivate.list => {
                    to.PutChar['(];
                    SS.Begin[to];
                        {ENABLE UNWIND => SS.End[to];
                        FOR l: ParseTreeList _ form.children, l.rest WHILE l # NIL DO
                            PrettyPrintParseTree[to, l.first];
                            IF l.rest # NIL THEN {to.PutChar[' ]; SS.Bp[to, FALSE, 0]}
                            ELSE IF breakLast THEN SS.Bp[to, FALSE, lastOffset];
                            ENDLOOP;
                        to.PutChar[')];
                        };
                    SS.End[to];
                    };
                ENDCASE => ERROR;
            };

        Print: PROC [to: IO.STREAM, pt: ParseTree] = {
            ubh: UB.Handle = UB.NewHandle[[stream[to]]];
            ss: IO.STREAM = SS.Create[ubh];
            PrettyPrintParseTree[ss, pt];
            ss.PutRope["\n"];
            ss.Close[];
            };

        }.