This ProBuilder code snippet demonstrates how to calculate and track profits separately for long and short trading positions within a trading strategy. The code identifies the type of trade (long or short) and updates the respective profit variables accordingly.

NOT TESTED:
ONCE LongStrategyProfit = 0
ONCE ShortStrategyProfit = 0
IF StrategyProfit <> StrategyProfit[1] THEN
    EntryPrice = TradePrice[2]
    ExitPrice = TradePrice[2]
    Difference = StrategyProfit - StrategyProfit[1]
    IF LongOnMarket[1] THEN
        //LONG trades
        LongStrategyProfit = LongStrategyProfit[1] + Difference
    ELSIF ShortOnmarket[1] THEN
        //SHORT trades
        ShortStrategyProfit = ShortStrategyProfit[1] + Difference
    ELSE
        //UNDEFINED trades for which both the Difference and the Entry and Exit prices need to be compared to determine the direction
        IF Difference > 0 THEN
            IF ExitPrice > EntryPrice THEN
                LongStrategyProfit = LongStrategyProfit[1] + Difference //when it's a PROFIT, a higher EXIT price implies a LONG trade
            ELSE
                ShortStrategyProfit = ShortStrategyProfit[1] + Difference //when it's a PROFIT, a lower EXIT price implies a SHORT trade
            ENDIF
        ELSE
            IF ExitPrice < EntryPrice THEN
                LongStrategyProfit = LongStrategyProfit[1] + Difference //when it's a LOSS, a lower EXIT price implies a LONG trade
            ELSE
                ShortStrategyProfit = ShortStrategyProfit[1] + Difference //when it's a LOSS, a higher EXIT price implies a SHORT trade
            ENDIF
        ENDIF
    ENDIF
ENDIF
graph LongStrategyProfit coloured("Green")
graph ShortStrategyProfit coloured("Red")
graph LongStrategyProfit + ShortStrategyProfit

Explanation of the Code:

• The code initializes two variables, LongStrategyProfit and ShortStrategyProfit, to zero using the ONCE keyword, ensuring they are set only once and retain their values throughout the execution.
• It checks if the overall strategy profit has changed (StrategyProfit <> StrategyProfit[1]). If it has, it calculates the profit difference and updates the respective long or short profit variables based on the type of trade.
• If the trade type is not directly known (LongOnMarket or ShortOnMarket), the code determines the trade type by comparing the entry and exit prices relative to the profit or loss situation.
• The results are then graphed, with long strategy profits in green and short strategy profits in red, providing a visual representation of the strategy's performance.

This snippet is useful for traders and developers looking to analyze the performance of trading strategies by distinguishing between profits made on long and short positions.