Originally Posted by
molot0v
Only a massochist would write in this inconsistent, all but useless, slow, ungainly, inelegant language.
It’s not the language that is inconsistent, slow, ungainly and inelegant, but your code. I have checked your original code again and found the following problems:
Code:
var count = 0;
var holder = new Array(99);
function addSelectEntry() {
document.frmLib.elements.options[document.frmLib.elements.options.length] = new Option(this.label, this.id, false, false);
}
function makeNewReadingObject(label, value, description) {
holder[count] = new readingObject(label, value, description, count);
count++;
}
function readingObject(label, value, description, id) {
this.label = label;
this.id = count;
count++;
this.value = value;
this.description = description;
this.section = -1;
this.addSelectEntry;
this.getDesc;
addSelectEntry();
}
readingObject.prototype.getDesc = function ( ) {
return this.description;
}
function buttonRemoveEntry() {
box = document.frmLib.elements;
id = box.options[box.selectedIndex].value;
for ( i = 0; i < box.options.length; i++ ) {
if ( box.options[i].value == id ) {
document.frmLib.elements.options[i] = null;
}
}
}
function updateInfo() {
box = document.frmLib.elements;
id = box.options[box.selectedIndex].value;
for ( i = 0; i < box.options.length; i++ ) {
if ( box.options[i].value == id ) {
return holder[document.frmLib.elements.options[i].value].description;
}
}
return false;
}
id = This parameter is never used.
count++; = You have already incremented count in the readingObject() initialisation code. Consequently, using makeNewReadingObject() messes up the holdArray() by skipping indexes.
this.addSelectEntry; = There is no use defining this, because it goes unused.
this.getDesc; = There is no need to define this here, because you declare it with readingObject.prototype.getDesc.
. . .
Before looking back at your old code again I took the liberty of re-writing it using some better OOP techniques:
Code:
// This object defines a single readingObject.
// . . .
function readingObject ( label, value, description, id, counter ) {
this.unique_id = counter;
this.label = label;
this.value = value;
this.description = description;
this.id = id;
this.section = -1;
this.getDesc = function ( ) {
return this.description;
}
this.addSelectEntry = function ( ) {
// Commented out for testing
// document.frmLib.elements.options [ document.frmLib.elements.options.length ] = new Option ( this.label, this.id, false, false );
}
this.addSelectEntry ( );
}
// This object defines a collection of readingObject's. Use the Add()
// function to add a new object into the holdArray.
// . . .
function readingObjectCollection ( ) {
this.holdArray = new Array ( );
this.Count = function ( ) {
return this.holdArray.length;
}
this.Add = function ( label, value, description, id ) {
this.holdArray [ this.Count ( ) ] = new readingObject ( label, value, description, id, this.Count ( ) );
}
this.InspectByIndex = function ( index ) {
// Returns null if an invalid index was specified.
return ( this.Count ( ) > 0 && index >= 0 && index < this.Count ( ) ) ? this.holdArray [ index ] : null;
}
// Why not add some more complex array-inspection functions
// while we're here...
// . . .
this.InspectByLabel = function ( label ) {
for ( var i = 0 ; i < this.holdArray.length ; i ++ ) {
if ( this.holdArray [ i ].label == label ) {
return this.holdArray [ i ];
}
}
// The loop fell-through; no readingObject was found with
// the specified label, so return null.
return null;
}
}
var oROC = new readingObjectCollection ( );
// Note that I have omitted the someid* parameters. This is because
// they were never used in your original implementation of the
// readingObject.
// EDIT - You can disregard the above comment.
oROC.Add ( 'somelabel0', 'someval0', 'somedesc0', 'someid0' );
oROC.Add ( 'somelabel1', 'someval1', 'somedesc1', 'someid1' );
oROC.Add ( 'somelabel2', 'someval2', 'somedesc2', 'someid2' );
// Some tests...
alert ( oROC.InspectByIndex ( 2 ).label );
alert ( oROC.InspectByLabel ( 'somelabel1' ).id );
I tested this and it works fine. I hope you can learn something from it, and don’t be too quick to slate JavaScript in future. 
More can be done with it than you could ever believe.
I'm more interested in getting the object array to work properly at the moment though 
Actually, for an interpreted language, javascript is relatively robust. Yes, there are many features I would like to see implemented (one being access to the heap) but I would never say that it was 'slow, ungainly, ...inelegant'. All of those adjectives are more reflective of the coder and his/her abilities, not the language per se.
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