alasql/src/69while.js

AlaSQL.js - JavaScript SQL database library for relational and graph data manipulation with support of localStorage, IndexedDB, and Excel

/*
//
// CREATE VIEW for Alasql.js
// Date: 03.11.2014
// (c) 2014, Andrey Gershun
//
*/

yy.While = function (params) { return yy.extend(this, params); }
yy.While.prototype.toString = function() {
	var s = 'WHILE ';
	s += this.expression.toString();
	s += ' '+this.loopstat.toString();
	return s;
};

yy.While.prototype.execute = function (databaseid,params,cb) {
	var self = this;
	var res = [];
//	console.log(this.expression.toJavaScript());
	var fn = new Function('params,alasql,p','return '+this.expression.toJavaScript());
//	console.log('cb',!!cb);
	if(cb) {
		var first = false;
		loop();
		function loop(data) {
			if(first) {
				res.push(data);
			} else {
				first = true;
			};
			setTimeout(function(){
				if(fn(params,alasql)) {
					self.loopstat.execute(databaseid,params,loop);
				} else {
					res = cb(res);
				}
			},0);
		}		
	} else {
		while(fn(params,alasql)) {
			var res1 = self.loopstat.execute(databaseid,params); 
			res.push(res1);
		}
	}
	return res;
};

yy.Break = function (params) { return yy.extend(this, params); }
yy.Break.prototype.toString = function() {
	var s = K('BREAK');
	return s;
};

yy.Break.prototype.execute = function (databaseid,params,cb,scope) {
	var res = 1;
	if(cb) res = cb(res);
	return res;
};

yy.Continue = function (params) { return yy.extend(this, params); }
yy.Continue.prototype.toString = function() {
	var s = K('CONTINUE');
	return s;
};

yy.Continue.prototype.execute = function (databaseid,params,cb,scope) {
	var res = 1;
	if(cb) res = cb(res);	
	return res;
};

yy.BeginEnd = function (params) { return yy.extend(this, params); }
yy.BeginEnd.prototype.toString = function() {
	var s = K('BEGIN')+' '+this.statements.toString()+' '+K('END');
	return s;
};

yy.BeginEnd.prototype.execute = function (databaseid,params,cb,scope) {
	var self = this;
	var res = [];

	var idx = 0;
	runone();
	function runone() {
		self.statements[idx].execute(databaseid,params,function(data){
			res.push(data);
			idx++;
			if(idx<self.statements.length) return runone();
			if(cb) res = cb(res);
		});
	}
	return res;
};