README.md
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	# @webassemblyjs/wasm-edit

	> Rewrite a WASM binary

	Replace in-place an AST node in the binary.

	## Installation

	```sh
	yarn add @webassemblyjs/wasm-edit
	```

	## Usage

	Update:

	```js
	import { edit } from "@webassemblyjs/wasm-edit";

	const binary = [/.../];

	const visitors = {
	ModuleImport({ node }) {
	node.module = "foo";
	node.name = "bar";
	}
	};

	const newBinary = edit(binary, visitors);
	```

	Replace:

	```js
	import { edit } from "@webassemblyjs/wasm-edit";

	const binary = [/.../];

	const visitors = {
	Instr(path) {
	const newNode = t.callInstruction(t.indexLiteral(0));
	path.replaceWith(newNode);
	}
	};

	const newBinary = edit(binary, visitors);
	```

	Remove:

	```js
	import { edit } from "@webassemblyjs/wasm-edit";

	const binary = [/.../];

	const visitors = {
	ModuleExport({ node }) {
	path.remove()
	}
	};

	const newBinary = edit(binary, visitors);
	```

	Insert:

	```js
	import { add } from "@webassemblyjs/wasm-edit";

	const binary = [/.../];

	const newBinary = add(actualBinary, [
	t.moduleImport("env", "mem", t.memory(t.limit(1)))
	]);
	```

	## Providing the AST

	Providing an AST allows you to handle the decoding yourself, here is the API:

	```js
	addWithAST(Program, ArrayBuffer, Array<Node>): ArrayBuffer;
	editWithAST(Program, ArrayBuffer, visitors): ArrayBuffer;
	```

	Note that the AST will be updated in-place.