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blockly > utils > extensions > register
utils.extensions.register() function
Registers a new extension function. Extensions are functions that help initialize blocks, usually adding dynamic behavior such as onchange handlers and mutators. These are applied using Block.applyExtension(), or the JSON "extensions" array attribute.
Signature:
export declare function register<T extends Block>(name: string, initFn: (this: T) => void): void;
Parameters
Parameter |
Type |
Description |
name |
string |
The name of this extension. |
initFn |
(this: T) => void |
The function to initialize an extended block. |
Returns:
void
Exceptions
{Error} if the extension name is empty, the extension is already registered, or extensionFn is not a function.
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Last updated 2025-05-16 UTC.
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