filter out defined variables in error

envconf.go

@@ -104,6 +104,7 @@ func (c *Config) Parse() {
 	}
 	for k, v := range c.env {
 		if failed && (v.parsed.err == nil) {
+			if v.empty {
 				if v.unset {
 					v.parsed.err = errors.New(fmt.Sprintf(`Environment variable "%s" not found. It should have been of type %s.`, k, v.dtype))
 					c.env[k] = v
@@ -114,6 +115,7 @@ func (c *Config) Parse() {
 			}
 		}
 	}
+}
 
 // Status prints out failures that occured while parsing the environment to os.Stderr.
 // Variables that have been defined without a default value and are