Get rid of checks when creating constructs. Check should handle this.

atom.go

@@ -2,6 +2,7 @@ package atom
 
 import (
 	"fmt"
+	"html"
 	"mime"
 	"regexp"
 	"strings"
@@ -10,6 +11,10 @@ import (
 	"golang.org/x/text/language"
 )
 
+func Unescape(s string) string {
+	return html.UnescapeString(s)
+}
+
 // isValidIRI checks whether an IRI is valid or not. It returns a bool.
 // https://www.w3.org/2011/04/XMLSchema/TypeLibrary-IRI-RFC3987.xsd
 func isValidIRI(iri string) bool {
@@ -17,6 +22,15 @@ func isValidIRI(iri string) bool {
 	return regexp.MustCompile(pattern).MatchString(iri)
 }
 
+// NewIRI creates a new IRI. It returns a string and an error.
+func NewIRI(iri string) (string, error) {
+	if !isValidIRI(iri) {
+		return "", fmt.Errorf("iri %v not correctly formatted", iri)
+	}
+
+	return iri, nil
+}
+
 // isCorrectlyEscaped checks whether a string is correctly escaped as per
 // RFC4287. It returns a bool.
 func isCorrectlyEscaped(text string) bool {
@@ -69,12 +83,31 @@ func isValidMediaType(m string) bool {
 	return true
 }
 
+// NewMediaType creates a new MediaType. It returns a string and an error.
+func NewMediaType(m string) (string, error) {
+	if !isValidMediaType(m) {
+		return "", fmt.Errorf("media type %v invalid", m)
+	}
+
+	mediaType, _, _ := mime.ParseMediaType(m)
+	return mediaType, nil
+}
+
 // isValidLanguageTag checks whether a LanguageTag is valid. It returns a bool.
 func isValidLanguageTag(languageTag string) bool {
 	_, err := language.Parse(languageTag)
 	return err == nil
 }
 
+// NewLanguageTag creates a new LanguageTag. It returns a string and an error.
+func NewLanguageTag(l string) (string, error) {
+	if !isValidLanguageTag(l) {
+		return "", fmt.Errorf("language tag %v invalid", l)
+	}
+
+	return l, nil
+}
+
 // isValidAttribute checks whether an Attribute is valid. It returns a bool.
 func isValidAttribute(attribute string) bool {
 	regex := regexp.MustCompile(`^[a-zA-Z0-9_]+="[^"]*"$`)