I'm trying to port an algorithm from Python to Go. The central part of it is a tree built using dicts, which should stay this way since each node can have an arbitrary number of children. All leaves are at the same level, so up the the lowest level the dicts contain other dicts, while the lowest level ones contain floats. Like this:
tree = {}
insert(tree, ['a', 'b'], 1.0)
print tree['a']['b']
So while trying to port the code to Go while learning the language at the same time, this is what I started with to test the basic idea:
func main() {
tree := make(map[string]interface{})
tree["a"] = make(map[string]float32)
tree["a"].(map[string]float32)["b"] = 1.0
fmt.Println(tree["a"].(map[string]float32)["b"])
}
This works as expected, so the next step was to turn this into a routine that would take a "tree", a path, and a value. I chose the recursive approach and came up with this:
func insert(tree map[string]interface{}, path []string, value float32) {
node := path[0]
l := len(path)
switch {
case l > 1:
if _, ok := tree[node]; !ok {
if l > 2 {
tree[node] = make(map[string]interface{})
} else {
tree[node] = make(map[string]float32)
}
}
insert(tree[node], path[1:], value) //recursion
case l == 1:
leaf := tree
leaf[node] = value
}
}
This is how I imagine the routine should be structured, but I can't get the line marked with "recursion" to work. There is either a compiler error, or a runtime error if I try to perform a type assertion on tree[node]
. What would be the correct way to do this?