Runs a callback everytime a new object is attached to a given node.
The callback can optionally return a disposer which will be run when the child is detached.
The optional options parameter accepts an object with the following options:
deep: boolean (default: false) - true if the callback should be run for all children deeply
or false if it it should only run for shallow children.
fireForCurrentChildren: boolean (default: true) - true if the callback should be immediately
called for currently attached children, false if only for future attachments.
Returns a disposer, which has a boolean parameter which should be true if pending detachment
callbacks should be run or false otherwise.
Parameters
target: ()=>object
Function that returns the object whose children should be tracked.
fn: (child:object)=>void| (()=>void)
Callback called when a child is attached to the target object.
Runs a callback everytime a new object is attached to a given node. The callback can optionally return a disposer which will be run when the child is detached.
The optional options parameter accepts an object with the following options:
deep: boolean(default:false) - true if the callback should be run for all children deeply or false if it it should only run for shallow children.fireForCurrentChildren: boolean(default:true) - true if the callback should be immediately called for currently attached children, false if only for future attachments.Returns a disposer, which has a boolean parameter which should be true if pending detachment callbacks should be run or false otherwise.