Controlling table column alignment using variable

Question

Hi I'm new to Javascript, having only used Applescript before.
I'm using Indesign 5.5 on Mac and I'm learning Javascript by adapting old Applescripts that I have been using for years.
So, with an existing table, one of the things I want to do is to set the alignments in the columns using a varible. Here's what I've tried so far:
function setColumnWidthsAndAlignments()
    var myWidths=[29, 23, 13, 13, 13, 13];
    var myAlignments=["leftAlign","leftAlign","centerAlign","centerAlign","rightAlign","rightAlign"];
    var numberOfColumns=myTable.columns.count();
    for (c=0;c<numberOfColumns;c++)
        myTable.columns[c].width=myWidths[c];
        myTable.columns[c].cells.everyItem().texts.everyItem().justification=Justification.myAlignments[c];
but I get an error
-- Object does not support the property or method 'myAlignments' --
If I discard the variable myAlignments and just put leftAlign for example, it works, so maybe I'm not declaring the variable properly?
I know I could add a few extra paragraph styles and cell styles and style the table that way, but I though this would be a good learning exercise (besides which I want to limit the number of paragraph styles in the document - there are enough already!)
If anybody is really interested, I'd like to place the whole script here and would really welcome any feedback on how the structure could be improved or optimised or just tell me if I'm heading in the right direction.
Thanks and regards,
Malcolm
//Simple table script 1
app.scriptPreferences.userInteractionLevel = UserInteractionLevels.interactWithAll; //make sure that user interactivity is switched on ????  why????
if(checkForOpenDocs()) //checks to see if there are any open Indesign documents
        if(targetMyTable()) //checks to see if the selection is inside a table - if not, gives an error dialog - if it is, returns variable myTable which can be used to target different parts of the table
               // selectLastRow();
                //resetTable();
                //applyTableTextParaStyle();
                //removeRules();
                //applyAlternatingFills();
                setColumnWidthsAndAlignments();
                //setRowHeightsAndInsets();
function checkForOpenDocs()
    if (app.documents.length!=0)   //there is at least one document open
        myDocument = app.documents.item(0);    //get the id of the frontmost document - might be useful?
        return true;
    else
        alert("There are no documents open");
        return false;
function targetMyTable() //no matter what is selected in the table, change selection to be whole table
    if(app.selection[0]==null) //if there is nothing selected
        alert("There is nothing selected.");
        return false
    var mySelection = app.selection[0];
    switch(mySelection.constructor.name)
                                        //When a row, a column, or a range of cells is
                                        //selected, the type returned is always "Cell"
        case "Cell":
        myTable=mySelection.parent;
        return true
        break;
        case "Table":
        myTable=mySelection;
        return true
        break;
        case "InsertionPoint":
        case "Character":
        case "Word":
        case "TextStyleRange":
        case "Line":
        case "Paragraph":
        case "TextColumn":
        case "Text":
        if(app.selection[0].parent.constructor.name == "Cell")
            myTable=mySelection.parent.parent;
            return true
        else
            alert("The selection is not inside a table.");
            return false
        break;
        case "Rectangle":
        case "Oval":
        case "Polygon":
        case "GraphicLine":
        case "TextFrame":
        if(app.selection[0].parent.parent.constructor.name == "Cell")
            myTable=mySelection.parent.parent.parent;
            return true
        else
            alert("The selection is not inside a table.");
            return false
        break;
        case "Image":
        case "PDF":
        case "EPS":
        if(app.selection[0].parent.parent.parent.constructor.name == "Cell")
            myTable=mySelection.parent.parent.parent.parent;
            return true
        else
            alert("The selection is not inside a table.");
            return false
        break;
        default:
        break;
function resetTable()
    myTable.cells.everyItem().clearCellStyleOverrides (true);  
function selectLastRow()
    //myTable.cells.itemByRange(0,-1).select();
    myTable.rows.itemByRange(-1,-1).select();
function applyTableTextParaStyle()
    myParagraphStyle=myDocument.paragraphStyles.item("•table text");
    myTable.cells.everyItem().texts.everyItem().appliedParagraphStyle = myParagraphStyle;
function removeRules()
    myTable.cells.everyItem().topEdgeStrokeWeight=0;
    myTable.cells.everyItem().bottomEdgeStrokeWeight=0;
    myTable.cells.everyItem().leftEdgeStrokeWeight=0;
    myTable.cells.everyItem().rightEdgeStrokeWeight=0;
function applyAlternatingFills()
    myColor=myDocument.swatches.item("Black");
    myTable.alternatingFills=AlternatingFillsTypes.alternatingRows;
    myTable.startRowFillColor=myColor;
    myTable.startRowFillTint=20;
    myTable.endRowFillColor=myColor;
    myTable.endRowFillTint = 0;
function setColumnWidthsAndAlignments()
    var myWidths=[29, 23, 13, 13, 13, 13];
    var myAlignments=["leftAlign","leftAlign","centerAlign","centerAlign","rightAlign","rightAlign"];
    var numberOfColumns=myTable.columns.count();
    for (c=0;c<numberOfColumns;c++)
        myTable.columns[c].width=myWidths[c];
        myTable.columns[c].cells.everyItem().texts.everyItem().justification=Justification.myAlignments[c];
function setRowHeightsAndInsets()
    myTable.rows.everyItem().minimumHeight=1.058;
    myInset=0.5;
    myTable.rows.everyItem().topInset=myInset;
    myTable.rows.everyItem().bottomInset=myInset;

Answer 1

You'd probably have more luck trying something like:
var myAlignments = [Justification.LEFT_ALIGN, Justification.LEFT_ALIGN,
Justification.CENTER_ALIGN etc.]
and then in the other line: ...texts.everyItem().justification =
myAlignments[c];
Alternatively, you could try keeping it as you have it, but perhaps
changing it to this:
texts.everyItem().justification = eval("Justification."+myAlignments[c]);...
which just creates a string and then runs it with eval.
At any rate, the problem as I see it with what you have is that you
myAlignments is an array of strings, and you cannot access a property of
an object (in this case Justification) with a dot+string. When you put
"Justification.leftAlign" and it works, I think that's because leftAlign
isn't acting as a string -- it's simply a property of the Justification
object.
Ariel