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Documentation Index

Fetch the complete documentation index at: https://docs.darvas.app/llms.txt

Use this file to discover all available pages before exploring further.

Message: Line limit exceeded (500). Oldest lines have been truncated.Cause: Your script created more than 500 Line entities. With dynamic keys like Line(\ph_$`, …)` on every bar, this fills up quickly on large bar counts.Fix: Only create lines on confirmed events (pivot detections, signals), not every bar. Or use a fixed pool of keys with extend: "right" and update them in place with .set():
// Bad: creates a new line on every bar
onBar(() => {
  Line(`line_${ctx.i()}`, { ... });
});

// Good: one line, updated in place
const trendLine = Line("trend", { x1: 0, y1: 0, x2: 1, y2: 1, color: "#22c55eFF" });
onBar(() => {
  trendLine.set({ x2: ctx.i(), y2: ctx.close() });
});
Message: Series limit exceeded (64).Cause: Your script created more than 64 Series instances (including internal ones created by ta.barssince and ta.cum).Fix: Count your Series. Reuse them where possible. Remember that each unique ta.barssince(key, ...) call takes one slot. Combine multiple related state variables into a single Series by encoding them (e.g. use one Series for price + another for index, not three for different values from the same event).
Message: LineFill source lines must have matching forceOverlay values.Cause: You created a LineFill using two Line entities with different forceOverlay settings - one with forceOverlay: true and the other with forceOverlay: false.Fix: Ensure both source lines have the same forceOverlay value:
const top = Line("top", { ..., forceOverlay: true });
const bot = Line("bot", { ..., forceOverlay: true }); // must match
const fill = LineFill("fill", top, bot, { color: "#22c55e30" });
Message: TypeError: X is not a function where X is a ctx.* accessor or ta.* call.Common causes:
  1. Calling ctx.close without parentheses when you want the value: use ctx.close() for the scalar, ctx.close for the source reference.
  2. Passing a scalar where a source function is required: ta.ema(ctx.close(), 20) passes a number, not a source.
Fix:
// Get the scalar value:
const closeValue = ctx.close();

// Get a source function reference (for ta.*):
const ema = ta.ema(ctx.close, 20); // correct - no parentheses on ctx.close
Symptom: A plot series appears blank or shows only a partial line with no visible values.Cause: The value emitted to plot() is NaN (often from an indicator in its warmup period, or from arithmetic on a null close value).Debug steps:
  1. Add console.log("value:", value) inside onBar and check the Console panel.
  2. Look for NaN or null in the output.
  3. Wrap with nz() or add an early if (na(value)) return guard.
onBar(() => {
  const rsi = ta.rsi(ctx.close, 14);
  console.log("RSI:", rsi); // will show NaN for first ~13 bars
  if (na(rsi)) return;
  plot("RSI", rsi);
});
Symptom: A Line or Box stops updating partway through the chart.Cause: You recreated the entity with the same key (new gen), but kept using the old handle returned from the first call. The old handle’s .set() calls silently no-op.Fix: Always capture the return value from the latest factory call:
// Wrong
const line = Line("sr", { ... });
onBar(() => {
  Line("sr", { ... }); // new gen - line handle is now stale
  line.set({ color: "red" }); // silently no-ops
});

// Correct
let line = Line("sr", { ... });
onBar(() => {
  line = Line("sr", { ... }); // reassign to get new handle
  line.set({ color: "red" }); // works
});
Message: TIMEOUT: top-level evaluation exceeded 1.5sCause: Top-level code (outside onBar) ran for too long. This usually means a large loop or expensive synchronous work at the script root.Fix: Move computation inside onBar. Only declarations (input.*, plot(), Series()) belong at the top level. If you genuinely need top-level computation, simplify it.
Message: TIMEOUT: onBar execution exceeded 50ms at bar NCause: One onBar call took more than 50ms. Usually caused by a nested loop over the entire bar history inside onBar.Fix: Replace manual loops with ta.* functions (Rust-native, much faster). See Performance tips.

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General debugging workflow

1

Check the Console panel

Open the Console tab in the editor. All console.log, console.warn, errors, and budget warnings appear here.
2

Add log statements

Add console.log("key:", value) at the top of onBar to see what values are flowing through. Remember: only the last 100 lines x 200 chars are shown.
3

Check for NaN with na()

If a plot is blank, add if (na(myValue)) console.log("NaN at bar", ctx.i()) to find the first bar where the value goes missing.
4

Isolate the indicator

Remove all but one plot and one calculation. Re-add them one by one until the problem reproduces.

Gotchas

Conceptual traps that cause these errors.

API limits

All budget numbers.

Performance tips

How to avoid timeout errors.