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התיעוד של RaamTrade
פתיחת RaamTrade

RC2_STATE_PARAM_CLASH

תוכן זה אינו זמין עדיין בשפה שלך.

<name> is already declared as a Param; it cannot also be persistent state.

What it means

A Param() is read-only for the lifetime of a run — its value is chosen by the optimizer, the walk-forward window, or the subscriber’s deploy form before the first bar, and every bar of that run sees the same number. Persistent state is the opposite: a slot your code writes.

One name cannot be both. If period = Param(20) is in the class body, self.period = 5 inside execute() is refused rather than silently shadowing the parameter the optimizer thinks it is sweeping.

Why it happens

class Bad(Strategy):
    period = Param(20, min=2, max=200)
    trade = Symbol()
    sizing = FixedCapital()


    def execute(self):
        self.period = 5        # ❌ period is a Param — read-only
        if self.trade.is_flat:
            self.buy(self.trade)

How to fix it

Give the state slot its own name and leave the Param alone.

class Good(Strategy):
    period = Param(20, min=2, max=200)
    trade = Symbol()
    sizing = FixedCapital()
    effective_period = 0


    def execute(self):
        sma = SMA(self.period, on=self.trade)


        self.effective_period = self.period     # ✅ a slot of its own
        if sma.value > 0 and self.trade.is_flat:
            self.buy(self.trade)

If what you actually wanted was a value that varies per bar, it was never a Param — declare it as state and drive it from the bar.