Pânico: atribuição à entrada no mapa nulo

// panic: assignment to entry in nil map
var m map[string]float64
m["pi"] = 3.1416

// You need to init map with "make" function
m := make(map[string]float64)

// Answer from https://yourbasic.org/golang/gotcha-assignment-entry-nil-map/
MaestroError