Debug message when relying on default values

[nicolasdscp]

Hello,

I have a question/suggestion, here's the context:

At my work we want to display a message (in stdout for example) when the Parser uses the default value.

Example:

type A struct {
  B int `env:"ENV_B" envDefault:"1"`
} 

func main() {
  a := A{}
  env.Parse(&a)
} 

If ENV_B is not defined, the parser will assign 1 to a.B, so is there a proper way to log anything at this moment ?
Like a debug message eg:

failed to parse ENV_B, relying on system default variable's value: 1

And if not, could such a feature be implemented ?

Thanks in advance

[caarlos0]

something like #185 maybe?

[nicolasdscp]

Yeah it's perfect !