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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.

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Same-key recreate invalidates old handles

If you call Line("my-line", opts) twice, the second call allocates a new generation. Any handle from the first call silently no-ops on .set() or .delete() - its generation no longer matches the slot. 
// Wrong: handle is stale after recreate
const line = Line("sr", { x1: 0, y1: 100, x2: 10, y2: 100, color: "#22c55eFF" });
Line("sr", { x1: 0, y1: 95, x2: 10, y2: 95, color: "#ef4444FF" }); // new gen
line.set({ color: "#a78bfaFF" }); // SILENTLY no-ops - old gen

// Correct: always capture the new handle
let line = Line("sr", { x1: 0, y1: 100, x2: 10, y2: 100, color: "#22c55eFF" });
line = Line("sr", { x1: 0, y1: 95, x2: 10, y2: 95, color: "#ef4444FF" });
line.set({ color: "#a78bfaFF" }); // works

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LineFill source keys are immutable

A LineFill cannot be retargeted to different Line entities after creation. To change source lines, delete the fill and create a new one. 
// Wrong: trying to update source lines
fill.lineA = newLine; // LineFill fields are internal - this has no effect

// Correct: delete + recreate
fill.delete();
const fill2 = LineFill("my-fill", newLineA, newLineB, { color: "#22c55e30" });

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Silent NaN coordinate rendering

Assigning NaN, Infinity, or null to any coordinate in a Line, Box, Label, or Marker causes the entity to become invisible. No error is raised, no console warning - it just disappears. 
// If pivotHigh is NaN, this line becomes invisible silently
Line("ph", { x1: pivotBar, y1: pivotHigh, x2: ctx.i(), y2: pivotHigh, color: "#ef4444FF" });

// Guard first:
if (!na(pivotHigh)) {
  Line("ph", { x1: pivotBar, y1: pivotHigh, x2: ctx.i(), y2: pivotHigh, color: "#ef4444FF" });
}

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Persistent Marker vs per-bar plot circles

These look similar but behave completely differently:
Marker entityplot(..., { style: "circles" })
TypePersistent, keyedPer-bar time-series
CreationExplicit factory callEmitted every onBar
PositionFixed at creation coordinateOne dot per bar
Use caseManual annotation on specific barsAlgorithmic per-bar output
Mixing them up is a common source of confusion. Use Marker for annotations on specific confirmed historical bars; use plot circles for recurring computed signals.

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NaN arithmetic propagation

JavaScript NaN is infectious - any math operation on NaN returns NaN: 
NaN + 1     // NaN
NaN * 0     // NaN
NaN > 50    // false (comparison with NaN is always false)
NaN === NaN // false
Use na(x) or nz(x, fallback) to break the chain: 
const rsi = ta.rsi(ctx.close, 14);
const safe = nz(rsi, 50); // 50 during warmup, real value after

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plot() registration must be top-level

plot(name, null, opts) registers the plot series. If you only call plot(name, value) inside onBar without the top-level registration, the visual options (color, linewidth, style) default to chart theme values and can produce unexpected rendering. Always pair every onBar plot call with a top-level registration: 
// Top level: register with options
plot("RSI", null, { color: "#a78bfaFF", linewidth: 2 });

// onBar: emit value
onBar(() => {
  plot("RSI", ta.rsi(ctx.close, 14));
});

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Entity budget truncation is silent

When you exceed the 500-per-type or 1500-total entity limit, the oldest entities are silently truncated. The chart looks correct for recent bars but missing for old bars. Check the Console panel for budget warning messages.

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Handles are shallow

A handle { __key, __gen, __kind } does not hold the entity state - it holds a reference to the slot. Two handles pointing to the same key+gen both mutate the same underlying entity: 
const h1 = Line("x", { x1: 0, y1: 0, x2: 1, y2: 1, color: "#22c55eFF" });
const h2 = h1; // h2 is the same handle object
h2.set({ color: "#ef4444FF" }); // mutates the same entity
// h1's color is also now #ef4444FF - same entity

Troubleshooting

Error messages and fixes.

Entities overview

Slot model and handle API in depth.

NaN handling

na() and nz() reference.