Bug 209309 Show javascript errorposition
If a javascript expression has errors, the error message is shown in the last lines in the preview tab. But there is no info where the error occurs. In most cases you had to guess the error location. It would be very helpfull to display the error location.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/ExecutionContext.java
* operator, one LHS expression, and up to two expressions on RHS, i.e.,
	 * 
	 * testExpr operator operand1 operand2 or testExpr between 1 20
	 * 
	 * Now only support comparison between the same data type
	 * 
	 * @param expr
	 *            the conditional expression to be evaluated
	 * @return a boolean value (as an Object)
	 */
	public Object evaluateCondExpr( IConditionalExpression expr )
	{
		IScriptExpression testExpr = expr.getExpression( );
		if ( testExpr == null )
			return Boolean.FALSE;
		try
		{
			return ScriptEvalUtil.evalExpr( expr,
					scriptContext.getContext( ),
					scriptContext.getScope( ),
					null,
					0 );
		}
		catch ( Exception e )
		{
			log.log( Level.SEVERE, e.getMessage( ), e );
			addException( new EngineException(
					MessageConstants.INVALID_EXPRESSION_ERROR, expr, e ) );
			return Boolean.FALSE;
		}