Real Transpilation Examples

This page shows actual transpiler output to help understand the transformation process.

Example 1: Basic Variable Assignment

Input:

let sma = ta.sma(close, 20);

Transpiled Output:

const { close } = $.data;
const ta = $.ta;
const p0 = ta.param(close, undefined, 'p0');
const p1 = ta.param(20, undefined, 'p1');
const temp_1 = ta.sma(p0, p1, '_ta0');
$.let.glb1_sma = $.init($.let.glb1_sma, temp_1);

Key Transformations:

• Implicit imports injected (close, ta)
• Arguments wrapped in ta.param() with unique IDs (p0, p1)
• Function call receives unique call ID (_ta0)
• Nested call hoisted to temporary variable (temp_1)
• Variable renamed with scope prefix (glb1_sma)
• Assignment wrapped in $.init()

Example 2: Array Access and Assignment

Input:

let prev_close = close[1];
cc = close[2];

Transpiled Output:

const { close } = $.data;
$.let.glb1_prev_close = $.init($.let.glb1_prev_close, $.get(close, 1));
$.set($.let.glb1_cc, $.get(close, 2));

Key Transformations:

• close[1] → $.get(close, 1) (Pine Script semantics)
• cc = close[2] → $.set($.let.glb1_cc, $.get(close, 2))
• Series access translated to context methods

Example 3: Binary Operations

Input:

const green_candle = close > open;
const bull_bias = ema9 > ema18;

Transpiled Output:

const { close, open } = $.data;
$.const.glb1_green_candle = $.init($.const.glb1_green_candle, $.get(close, 0) > $.get(open, 0));
$.const.glb1_bull_bias = $.init($.const.glb1_bull_bias, $.get($.const.glb1_ema9, 0) > $.get($.const.glb1_ema18, 0));

Key Transformations:

• Binary operations preserve structure
• Series values extracted with $.get(series, 0)
• User variables accessed through context ($.const.glb1_ema9)

Example 4: Nested Function Calls (Expression Hoisting)

Input:

let d = ta.ema(math.abs(ap - 99), 10);

Transpiled Output:

const ta = $.ta;
const math = $.math;
const p0 = math.param($.get($.let.glb1_ap, 0) - 99, undefined, 'p0');
const temp_1 = math.abs(p0, '_math0');
const p1 = ta.param(temp_1, undefined, 'p1');
const p2 = ta.param(10, undefined, 'p2');
const temp_2 = ta.ema(p1, p2, '_ta0');

$.let.glb1_d = $.init($.let.glb1_d, temp_2);

Key Transformations:

• Nested math.abs(ap - 99) hoisted to temp_1
• Each function call isolated with unique IDs
• Inner function executed first, result passed to outer function
• Ensures proper execution order for stateful functions

Example 5: Scoped Variables (If Statement)

Input:

let aa = 0;
if (_cc > 1) {
    let bb = 1;
    aa = 1;
}

Transpiled Output:

$.let.glb1_aa = $.init($.let.glb1_aa, 0);
if ($.get($.const.glb1__cc, 0) > 1) {
    $.let.if2_bb = $.init($.let.if2_bb, 1); // Scoped to 'if2'
    $.set($.let.glb1_aa, 1); // Updates global scope
}

Key Transformations:

• Global variable: glb1_aa
• If-scoped variable: if2_bb (different prefix)
• Assignment to existing variable uses $.set()
• New variable declaration uses $.init()

Example 6: Equality Checks (NaN Handling)

Input:

if (avg_len === 0) {
    ret_val = cc[1];
}

Transpiled Output:

if ($.math.__eq($.get(avg_len, 0), 0)) {
    $.set($.let.fn2_ret_val, $.get($.let.fn2_cc, 1));
}

Key Transformations:

• === → $.math.__eq() (handles NaN == NaN correctly)
• Variables accessed with $.get()
• Assignment uses $.set()

Example 7: Array Pattern Destructuring

Input:

let [a, b] = ta.supertrend(close, 10, 3);

Transpiled Output:

const p0 = ta.param(close, undefined, 'p0');
const p1 = ta.param(10, undefined, 'p1');
const p2 = ta.param(3, undefined, 'p2');
const temp_1 = ta.supertrend(p0, p1, p2, '_ta0');

let a = $.init($.let.glb1_a, $.get($.const.glb1_temp_1, 0)[0]);
let b = $.init($.let.glb1_b, $.get($.const.glb1_temp_1, 0)[1]);

Key Transformations:

• Function call hoisted to temp_1
• Destructuring split into individual assignments
• Each element accessed via $.get(temp, 0)[index]
• Tuple convention: [[a, b]] returned by function, destructured here

Example 8: Array Expression in request.security

User Variables:

const o = open;
const c = close;
const [res, data] = await request.security('BTCUSDC', '240', [o, c], false, false);

Transpiled Output:

$.const.glb1_o = $.init($.const.glb1_o, open);
$.const.glb1_c = $.init($.const.glb1_c, close);
const p2 = request.param([$.get($.const.glb1_o, 0), $.get($.const.glb1_c, 0)], undefined, 'p2');
const temp_1 = await request.security('BTCUSDC', '240', p2, false, false);
// ... destructuring follows

Direct Series:

const [res, data] = await request.security('BTCUSDC', '240', [open, close], false, false);

Transpiled Output:

const p2 = request.param([open, close], undefined, 'p2');
const temp_1 = await request.security('BTCUSDC', '240', p2, false, false);
// ... destructuring follows

Key Transformations:

• User variables in arrays: [o, c] → [$.get(o, 0), $.get(c, 0)]
• Direct Series: [open, close] → passed through unchanged
• request.param() handles tuple detection internally

Example 9: For Loop with Scope

Input:

let sum = 0;
for (let i = 0; i < 10; i++) {
    sum += values[i];
}

Transpiled Output:

$.let.glb1_sum = $.init($.let.glb1_sum, 0);
for (let i = 0; i < 10; i++) {
    // Loop variable NOT transformed
    $.set($.let.glb1_sum, $.get($.let.glb1_sum, 0) + $.get($.let.glb1_values, i));
}

Key Transformations:

• Loop variable i remains unchanged (not a time-series)
• sum transformed to $.let.glb1_sum
• Compound assignment += becomes explicit get/set
• values[i] uses standard array access (not Pine Script semantics)

Data Flow Visualization

Variable Assignment Flow

User Code: let ema9 = ta.ema(close, 9);
                ↓
        Transpiler Analysis
                ↓
    ┌───────────────────────┐
    │ 1. Inject imports     │
    │    const { close } =  │
    │    $.data             │
    └───────────┬───────────┘
                ↓
    ┌───────────────────────┐
    │ 2. Wrap arguments     │
    │    p0 = ta.param(...) │
    │    p1 = ta.param(...) │
    └───────────┬───────────┘
                ↓
    ┌───────────────────────┐
    │ 3. Add call ID        │
    │    ta.ema(p0, p1,     │
    │    '_ta0')            │
    └───────────┬───────────┘
                ↓
    ┌───────────────────────┐
    │ 4. Hoist to temp      │
    │    temp_1 = ...       │
    └───────────┬───────────┘
                ↓
    ┌───────────────────────┐
    │ 5. Rename variable    │
    │    glb1_ema9          │
    └───────────┬───────────┘
                ↓
    ┌───────────────────────┐
    │ 6. Wrap in $.init()   │
    │    $.let.glb1_ema9 =  │
    │    $.init(...)        │
    └───────────────────────┘

Understanding the Transformation Rules

Original Pattern	Transformed Pattern	Reason
let x = value	$.let.scope_x = $.init(...)	State persistence
x = value	$.set($.let.scope_x, value)	Update current value
x[1]	$.get(x, 1)	Pine Script indexing
func(arg)	func(ns.param(arg, undefined, 'p0'), '_id')	Series wrapping + state isolation
a == b	$.math.__eq(a, b)	NaN comparison
const [a, b] = f()	Split into individual inits	Tuple destructuring