1package terraform 2 3// EvalNodeFilterFunc is the callback used to replace a node with 4// another to node. To not do the replacement, just return the input node. 5type EvalNodeFilterFunc func(EvalNode) EvalNode 6 7// EvalNodeFilterable is an interface that can be implemented by 8// EvalNodes to allow filtering of sub-elements. Note that this isn't 9// a common thing to implement and you probably don't need it. 10type EvalNodeFilterable interface { 11 EvalNode 12 Filter(EvalNodeFilterFunc) 13} 14 15// EvalFilter runs the filter on the given node and returns the 16// final filtered value. This should be called rather than checking 17// the EvalNode directly since this will properly handle EvalNodeFilterables. 18func EvalFilter(node EvalNode, fn EvalNodeFilterFunc) EvalNode { 19 if f, ok := node.(EvalNodeFilterable); ok { 20 f.Filter(fn) 21 return node 22 } 23 24 return fn(node) 25} 26