Add shortcode into the post text to show every value from Post, Term, User, Date, WP_Query, System and Option.
– [ (open tag)
– post (or user or option, required)
– : field name (required, native fields and meta are supported)
– : sub field key (optional and multiple, if field is array)
– | ID (optional, if omitted will take the current)
– ? Fallback text (optional, shown if field value is null)
– ] (close tag)