> For the complete documentation index, see [llms.txt](https://developer.singular.live/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.singular.live/composition-scripting/cheat-sheets/best-practices.md).
# Best practices
Use these cheat sheets to follow best practices in common scripting tasks.
### Communication between sub-compositions
An efficient option for exchanging data between sub-compositions is by adding functions to the composition object.
#### Receiving data in a sub-composition
Extend a composition object by adding the function comp.updateContent()
{% code title="Lower subcomposition Script" %}
```javascript
(function() {
return {
init: function(comp, context) {
console.log("Initialize Composition script " + comp.name);
// extend the composition object
// receive data in the updateContent function
comp.updateContent = function(data) {
console.log("updateContent() - data =", data);
}
},
close: function(comp, context) {
console.log("Close Composition script " + comp.name);
}
};
})();
```
{% endcode %}
#### Sending data to a sub-composition
Get reference to the receiving composition and send data by calling its updateContent() function.
{% code title="Root Script" %}
```javascript
((function() {
return {
init: function(comp, context) {
console.log("Initialize Composition script " + comp.name);
// get composition reference
const compLower = comp.find("Lower")[0];
comp.addListener('payload_changed', (event, msg, e) => {
console.log("Composition payload " + comp.name, event, msg);
const payload = comp.getPayload2();
// send data to destination
compLower.updateContent(payload);
e.stopPropagation();
});
},
close: function(comp, context) {
console.log("Close Composition script " + comp.name);
}
};
})();
```
{% endcode %}
### Updating overlay content from the composition script
A typical use case is receiving data in sub-composition control nodes, interpreting them, and updating properties within the sub-composition.
In such a case, it is recommended to unlink the receiving control nodes from properties and directly update widget properties.
#### **Reading control nodes, generating HTML, and updating the widget’s text property**
{% code title="Lower subcomposition Script" %}
```javascript
(function() {
return {
init: function(comp, context) {
console.log("Initialize Composition script " + comp.name);
const wiFullname = comp.findWidget("fullname")[0];
comp.addListener('payload_changed', (event, msg, e) => {
console.log("Composition payload " + comp.name, event, msg);
// read control nodes content
const p = comp.getPayload2();
const htmlText = `${p.firstname} ${p.lastname}`;
// update text widget
wiFullname.setPayload({
"text": htmlText
});
e.stopPropagation();
});
},
close: function(comp, context) {
console.log("Close Composition script " + comp.name);
}
};
})();
```
{% endcode %}
---
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