+//<script type="text/javscript">
+
+
+const XObject = imports.XObject.XObject;
+
+
+
+const console = imports.console.console;
+const Token = imports.Token.Token;
+const Lang = imports.Lang.Lang;
+
+
+/**
+ * @class TokenStream
+ *
+ * BC notes:
+ *
+ * nextT => nextTok
+ * lookT => lookTok
+ *
+ */
+
+
+const TokenStream = XObject.define(
+
+ /**
+ * @constructor
+ *
+ *
+ */
+
+ function(tokens) {
+
+
+ this.tokens = (tokens || []);
+ // Seed.print(this.tokens.length);
+ this.rewind();
+ },
+ Object,
+ {
+ cursor : -1, // where are we in the stream.
+
+ rewind : function() {
+ this.cursor = -1;
+ },
+
+ /**
+ @type JSDOC.Token
+ */
+ look : function(/**Number*/n, /**Boolean*/considerWhitespace) {
+ if (typeof n == "undefined") n = 0;
+
+ if (considerWhitespace == true) {
+ if (this.cursor+n < 0 || this.cursor+n > (this.tokens.length -1)) {
+ return new Token("", "VOID", "START_OF_STREAM");
+ }
+ return this.tokens[this.cursor+n];
+ }
+ else {
+ var count = 0;
+ var i = this.cursor;
+
+ while (true) {
+ if (i < 0) return new Token("", "VOID", "START_OF_STREAM");
+ else if (i > this.tokens.length) return new Token("", "VOID", "END_OF_STREAM");
+
+ if (i != this.cursor && (this.tokens[i] === undefined || this.tokens[i].is("WHIT"))) {
+ if (n < 0) i--; else i++;
+ continue;
+ }
+
+ if (count == Math.abs(n)) {
+ return this.tokens[i];
+ }
+ count++;
+ (n < 0)? i-- : i++;
+ }
+
+ return new Token("", "VOID", "STREAM_ERROR"); // because null isn't an object and caller always expects an object
+ }
+ },
+
+ lookFor : function (data)
+ {
+ // non tree version..
+ var i = this.cursor < 0 ? 0 : this.cursor ;
+
+ while (true) {
+ if (i >= this.tokens.length) return -1;
+ if (this.tokens[i].data == data) {
+ return i;
+ }
+ i++;
+
+ }
+ // should not get here!
+ return -1;
+
+ },
+
+
+ /**
+ * look ahead (or back) x number of tokens (which are not comment or whitespace)
+ * ?? used any more?
+ */
+ lookTok : function(/**Number*/n) {
+ if (typeof n == "undefined") n = 1;
+
+
+ var count = 0;
+ var i = this.cursor;
+
+ while (true) {
+ // print(i);
+ if (i < 0) {
+ if (n > -1) {
+ i = 0;
+ count++;
+ continue;
+
+ }
+ return new Token("", "VOID", "END_OF_STREAM");
+ }
+ else if (i > this.tokens.length) return new Token("", "VOID", "END_OF_STREAM");
+
+ if (i != this.cursor && (this.tokens[i] === undefined || this.tokens[i].is("WHIT") || this.tokens[i].is("COMM"))) {
+ if (n < 0) i--; else i++;
+ continue;
+ }
+
+ if (count == Math.abs(n)) {
+ return this.tokens[i];
+ }
+ count++;
+ (n < 0)? i-- : i++;
+ }
+ // should never get here..
+ return false; // because null isn't an object and caller always expects an object;
+
+ },
+
+ /**
+ * @return {Token|null}
+ * next token (with white space)
+ */
+
+
+ next : function(/**Number*/howMany) {
+ if (typeof howMany == "undefined") howMany = 1;
+ if (howMany < 1) return null;
+ var got = [];
+
+ for (var i = 1; i <= howMany; i++) {
+ if (this.cursor+i >= this.tokens.length) {
+ return null;
+ }
+ got.push(this.tokens[this.cursor+i]);
+ }
+ this.cursor += howMany;
+
+ if (howMany == 1) {
+ return got[0];
+ }
+ else return got;
+ },
+ // what about comments after 'function'...
+ // is this used ???
+ nextTok : function() {
+ return this.nextNonSpace();
+ },
+ nextNonSpace : function ()
+ {
+
+ while (true) {
+ tok = this.next(1);
+ if (!tok) {
+ return false;
+ }
+ if (tok.is('WHIT') || tok.is('COMM')) {
+ continue;
+ }
+ return tok;
+ }
+ },
+ /**
+ * @type JSDOC.Token[]
+ * @param start {String} token name or data (eg. '{'
+ * @param stop {String} (Optional) token name or data (eg. '}'
+ */
+ balance : function(/**String*/start, /**String*/stop) {
+
+
+ start = typeof(Lang.punc(start)) == 'undefined' ? start : Lang.punc(start);
+
+ if (!stop) stop = Lang.matching(start);
+
+ var depth = 0;
+ var got = [];
+ var started = false;
+ //Seed.print("START:" + start);
+ //Seed.print("STOP:" + stop);
+ while ((token = this.look())) {
+ if (token.is(start)) {
+ // Seed.print("balance: START : " + depth + " " + token.data);
+ depth++;
+ started = true;
+ }
+
+ if (started) {
+ got.push(token);
+ }
+
+ if (token.is(stop)) {
+ depth--;
+ // Seed.print("balance: STOP: " + depth + " " + token.data);
+ if (depth < 1) return got;
+ }
+ if (!this.next()) break;
+ }
+ return false;
+ },
+
+ getMatchingToken : function(/**String*/start, /**String*/stop) {
+ var depth = 0;
+ var cursor = this.cursor;
+
+ if (!start) {
+ start = Lang.matching(stop);
+ depth = 1;
+ }
+ if (!stop) stop = Lang.matching(start);
+
+ while ((token = this.tokens[cursor])) {
+ if (token.is(start)) {
+ depth++;
+ }
+
+ if (token.is(stop) && cursor) {
+ depth--;
+ if (depth == 0) return this.tokens[cursor];
+ }
+ cursor++;
+ }
+ return false;
+ },
+
+ insertAhead : function(/**JSDOC.Token*/token) {
+ this.tokens.splice(this.cursor+1, 0, token);
+ },
+
+ remaining : function() {
+ var ret = [];
+ while (true) {
+ var tok = this.look(1,true);
+ if (!tok || !tok.is || tok.is('VOID')) {
+ return ret;
+ }
+ ret.push(this.next(1));
+ }
+ },
+
+
+ arrayToString : function(ar) {
+ console.log(typeof(ar));
+ var ret = [];
+ ar.forEach(function(e) {
+ ret.push(e.data);
+ })
+ return ret.join('');
+ },
+ dump: function(start, end)
+ {
+ start = Math.max(start || 0, 0);
+ end = Math.min(end || this.tokens.length, this.tokens.length);
+ var out='';
+ for (var i =start;i < end; i++) {
+
+ out += (this.tokens[i].outData == false) ? this.tokens[i].data : this.tokens[i].outData;
+ };
+ print(out);
+ }
+});
+