"null" type for not required field

[feloy]

Hi,

I'm starting using jsonschema-go to define a JSON schema. thanks for this work :)

I can see that, when I declare a field as a pointer into a struct, to make it not required, the type "null" is added to the list of types for this field.

type MyObject struct {
	_ struct{} `additionalProperties:"false"`
	OptionalField *string `json:"optionalField"`
}

"optionalField": {
"type": [
      "null",
      "string"
     ]
  }

I would expect that the type is only "string" here, as the null value is covered by the not required capability.

[vearutop]

Hello, required keyword addresses the absence of a property, not its value. For example, for a schema

{"required":["foo"]}

values {"foo":null}, {"foo":123} would be valid,
but values {}, {"bar":null} would be invalid.