# Transformers (/developers/pinets/architecture/transpiler/transformers)



## Code Transformers [#code-transformers]

The transformation logic is split into specialized transformers found in `src/transpiler/transformers/`.

## WrapperTransformer [#wrappertransformer]

Ensures the user code is wrapped in a standard context function:

```javascript
(context) => {
    // user code
}
```

## NormalizationTransformer [#normalizationtransformer]

Prevents users from aliasing standard Pine Script symbols in import destructuring. This ensures the transpiler can reliably identify standard variables like `close` or `ta`.

## InjectionTransformer [#injectiontransformer]

Scans for usage of standard variables (like `close`, `open`) and injects the necessary destructuring statements if they are missing:

```javascript
const { close, open } = context.data;
```

## MainTransformer & StatementTransformer [#maintransformer--statementtransformer]

These handle the bulk of the logic:

* **Variable Declaration**: Transforms `let x = ...` into `$.let.scope_x = $.init(...)`.
* **Assignment**: Transforms `x = ...` into `$.set($.let.scope_x, ...)`.
* **Array Access**: Transforms `x[1]` into `$.get($.let.scope_x, 1)`.
* **Loops/Conditionals**: Ensures scoping rules are respected within blocks.

## ExpressionTransformer [#expressiontransformer]

Handles expressions, primarily function calls and binary operations.

* **Function Calls**: Injects `param()` wrappers around arguments.
* **Hoisting**: "Unwraps" nested calls. `ta.ema(ta.sma(close, 10), 10)` is transformed into:
  1. Calculate SMA -> temp var.
  2. Calculate EMA using temp var.
     This simplifies the generated code and ensures proper order of operations for stateful functions.