You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: listener.go
    path of file: ./repos/sliver/implant/vendor/github.com/tetratelabs/wazero/experimental
    
    the code of the file until where you have to start completion: package experimental

import (
	"context"

	"github.com/tetratelabs/wazero/api"
)

// StackIterator allows it
    
func (multi multiFunctionListenerFactory) NewFunctionListener(def api.FunctionDefinition) FunctionListener {
	var lstns []FunctionListener
	for _, factory := range multi {
		if lstn := factory.NewFunctionListener(def); lstn != nil {
			lstns = append(lstns, lstn)
		}
	}
	switch len(lstns) {
	case 0:
		return nil
	case 1:
		return lstns[0]
	default:
		return &multiFunctionListener{lstns: lstns}
	}
}