To write code for an Expert advisor

I am using (eabuilder.com) to build my expert advisor for practice. It has all the function I need except one

To restrict additional trades if any current is negative.

Example when trading EUSUSD I like to add more trades when trade is positive and I want the EA I built not to add any additional trades if any of the current trade(s) is negative. But if trades are positive it can continue to add more trade(s) as per the EA instructions.

The eabuilder.com website has a column to enter the codes for additional customize function.(see below)

double ExampleFunction()

{

   return(High[1] - Low[1]);

}

I want to be able to add this myself, I don't want to send my EA to a develop to add this function