commit 76045c518f76faa700d97c13875641bd500e7a83
Author: Charles Iliya Krempeaux <iamreiver@gmail.com>
Date:   Fri Aug 11 12:08:28 2023 -0700

    initial commits

diff --git a/mediarange/mediarange.go b/mediarange/mediarange.go
new file mode 100644
index 0000000..b23fb8a
--- /dev/null
+++ b/mediarange/mediarange.go
@@ -0,0 +1,196 @@
+package mediarange
+
+import (
+	"errors"
+	"strings"
+)
+
+var (
+	errBadMediaRange = errors.New("bad media-range")
+)
+
+// MediaRange represents a "media-range" as defined by IETF RFC-2616 (Hypertext Transfer Protocol — HTTP/1.1) in section 14.1.
+//
+// Here are some sample media-ranges:
+//
+//	*/*
+//	audio/*
+//	image/*
+//	text/*
+//	video/*
+//	application/x-tar
+//	audio/wav
+//	image/gif
+//	image/png
+//	text/html
+//	text/plain
+//	video/mp4
+//
+// Note that some of these sample media-ranges look like media-types / mime-types:
+//
+//	application/x-tar
+//	audio/wav
+//	image/gif
+//	image/png
+//	text/html
+//	text/plain
+//	video/mp4
+//
+// But some of these sample media-ranges are not media-types / mime-types:
+//
+//	*/*
+//	audio/*
+//	image/*
+//	text/*
+//	video/*
+//
+// These later kinds of media-ranges (that do not look like media-types / mime-types) use the asterisk ("*") as a wild-card symbol.
+// So "*/*" represents any media-type / mime-type.
+// ANd "image/*" represents "image/gif", "image/png", etc.
+type MediaRange struct {
+	typ string
+	subtyp string
+}
+
+// Create creates a MediaRange.
+//
+// For example:
+//
+//	// audio/ogg
+//	mediarange.Create("audio", "ogg")
+//
+//	// audio/*
+//	mediarange.Create("audio", "*")
+//
+//	// */*
+//	mediarange.Create("*", "*")
+//
+// Note that an empty string for mediaRangeType or mediaRangeSubType will be treated as a wild-card (i.e., "*").
+func Create(mediaRangeType string, mediaRangeSubType string) MediaRange {
+	mediaRangeType = strings.TrimSpace(mediaRangeType)
+	mediaRangeSubType = strings.TrimSpace(mediaRangeSubType)
+
+	if "*" == mediaRangeType {
+		mediaRangeType = ""
+	}
+	if "*" == mediaRangeSubType {
+		mediaRangeSubType = ""
+	}
+
+	return MediaRange{
+		typ:    strings.ToLower(mediaRangeType),
+		subtyp: strings.ToLower(mediaRangeSubType),
+	}
+}
+
+// Parse parses a string and returns a MediaRange.
+//
+// For example:
+//
+//	mr, err := mediarange.Parse("application/activity+json")
+func Parse(value string) (MediaRange, error) {
+
+	value = strings.TrimSpace(value)
+
+	parts := strings.SplitN(value, "/", 2)
+	if 2 != len(parts) {
+		return MediaRange{}, errBadMediaRange
+	}
+
+	var typ string = parts[0]
+
+	var subtyp string
+	{
+		a := strings.SplitN(parts[1], ";", 2)
+		{
+			length := len(a)
+			if 2 != length && 1 != length {
+				return MediaRange{}, errBadMediaRange
+			}
+		}
+
+		subtyp = a[0]
+	}
+
+	return Create(typ, subtyp), nil
+}
+
+// SubType returns the subtype of the media-range in its canonical form — i.e. lower-case and without spacing.
+func (receiver MediaRange) SubType() string {
+	var typ string = receiver.typ
+	var subtyp string = receiver.subtyp
+
+	if "" == typ || "*" == typ  {
+		return "*"
+	}
+
+	if "" == subtyp {
+		return "*"
+	}
+
+	return subtyp
+}
+
+// Type returns the type of the media-range in its canonical form — i.e. lower-case and without spacing.
+func (receiver MediaRange) Type() string {
+	var typ string = receiver.typ
+
+	if "" == typ {
+		return "*"
+	}
+
+	return typ
+}
+
+func (receiver MediaRange) Match(value string) bool {
+
+	var typ string = receiver.Type()
+	if "*" == typ {
+		return true
+	}
+
+	// Since media-types are a sub-set of media-ranges, we can do this.
+	var mediatype MediaRange
+	{
+		var err error
+
+		mediatype, err = Parse(value)
+		if nil != err {
+			return false
+		}
+	}
+
+	if mediatype.typ != typ  {
+		return false
+	}
+
+	var subtyp string = receiver.SubType()
+	if "*" == subtyp {
+		return true
+	}
+
+	if mediatype.subtyp != subtyp {
+		return false
+	}
+
+	return true
+}
+
+// String returns the serialed media-range.
+//
+// For example:
+//
+//	"text/html" == mediarange.Create("text", "html").String()
+func (receiver MediaRange) String() string {
+	var p []byte
+
+	var typ string = receiver.Type()
+	p = append(p, typ...)
+
+	p = append(p, '/')
+
+	var subtyp string = receiver.SubType()
+	p = append(p, subtyp...)
+
+	return string(p)
+}
diff --git a/mediarange/mediarange_match_test.go b/mediarange/mediarange_match_test.go
new file mode 100644
index 0000000..e872010
--- /dev/null
+++ b/mediarange/mediarange_match_test.go
@@ -0,0 +1,594 @@
+package mediarange_test
+
+import (
+	"sourcecode.social/reiver/go-httpaccept/mediarange"
+
+	"testing"
+)
+
+func TestMediaRange_Match(t *testing.T) {
+
+	tests := []struct{
+		MediaType string
+		MediaRange mediarange.MediaRange
+		Expected bool
+	}{
+		{
+			MediaType: "application/activity+json",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/epub+zip",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/gzip",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/json",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/pdf",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/msword",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/octet-stream",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/ogg",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/rtf",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/xhtml+xml",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/x-httpd-php",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "application/X-httpd-PHP",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "image/gif",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "image/png",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "Image/png",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "image/PnG",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "IMAGE/PNG",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "text/html",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "TEXT/html",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "text/plain",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "TEXT/PLAIN",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+		{
+			MediaType: "xyz/banana",
+			MediaRange: mediarange.Create("", ""),
+			Expected: true,
+		},
+
+
+
+		{
+			MediaType: "application/activity+json",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/epub+zip",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/gzip",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/json",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/pdf",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/msword",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/octet-stream",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/ogg",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/rtf",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/xhtml+xml",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/x-httpd-php",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/X-httpd-PHP",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/gif",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/png",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "Image/png",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/PnG",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "IMAGE/PNG",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "text/html",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "TEXT/html",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "text/plain",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "TEXT/PLAIN",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "xyz/banana",
+			MediaRange: mediarange.Create("*", "*"),
+			Expected: true,
+		},
+
+
+
+		{
+			MediaType: "application/activity+json",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/epub+zip",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/gzip",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/json",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/pdf",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/msword",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/octet-stream",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/ogg",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/rtf",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/xhtml+xml",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/x-httpd-php",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "application/X-httpd-PHP",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/gif",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "image/png",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "Image/png",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "image/PnG",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "IMAGE/PNG",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "text/html",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "TEXT/html",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "text/plain",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "TEXT/PLAIN",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "xyz/banana",
+			MediaRange: mediarange.Create("application", "*"),
+			Expected: false,
+		},
+
+
+
+		{
+			MediaType: "application/activity+json",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/epub+zip",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/gzip",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/json",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/pdf",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/msword",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/octet-stream",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/ogg",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/rtf",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/xhtml+xml",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/x-httpd-php",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/X-httpd-PHP",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "image/gif",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/png",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "Image/png",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/PnG",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "IMAGE/PNG",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: true,
+		},
+		{
+			MediaType: "text/html",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "TEXT/html",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "text/plain",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "TEXT/PLAIN",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+		{
+			MediaType: "xyz/banana",
+			MediaRange: mediarange.Create("image", "*"),
+			Expected: false,
+		},
+
+
+
+		{
+			MediaType: "application/activity+json",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/epub+zip",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/gzip",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/json",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/pdf",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/msword",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/octet-stream",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/ogg",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/rtf",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/xhtml+xml",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/x-httpd-php",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "application/X-httpd-PHP",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "image/gif",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "image/png",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: true,
+		},
+		{
+			MediaType: "Image/png",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: true,
+		},
+		{
+			MediaType: "image/PnG",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: true,
+		},
+		{
+			MediaType: "IMAGE/PNG",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: true,
+		},
+		{
+			MediaType: "text/html",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "TEXT/html",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "text/plain",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "TEXT/PLAIN",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+		{
+			MediaType: "xyz/banana",
+			MediaRange: mediarange.Create("image", "png"),
+			Expected: false,
+		},
+	}
+
+	for testNumber, test := range tests {
+
+		actual := test.MediaRange.Match(test.MediaType)
+		expected := test.Expected
+
+		if expected != actual {
+			t.Errorf("For test #%d, the actual result from trying to match the media-type against the media-range is not what was expected.", testNumber)
+			t.Logf("MEDIA-TYPE:  %q", test.MediaType)
+			t.Logf("MEDIA-RANGE: %q", test.MediaRange)
+			t.Logf("EXPECTED: %t", expected)
+			t.Logf("ACTUAL:   %t", actual)
+			continue
+		}
+	}
+}
diff --git a/mediarange/mediarange_parse_test.go b/mediarange/mediarange_parse_test.go
new file mode 100644
index 0000000..f1814a0
--- /dev/null
+++ b/mediarange/mediarange_parse_test.go
@@ -0,0 +1,286 @@
+package mediarange_test
+
+import (
+	"sourcecode.social/reiver/go-httpaccept/mediarange"
+
+	"testing"
+)
+
+func TestParse(t *testing.T) {
+
+	tests := []struct{
+		MediaRange string
+		Expected mediarange.MediaRange
+	}{
+		{
+			MediaRange:                 "*/*",
+			Expected: mediarange.Create("*", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "*/*;q=0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=0.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=0.5",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=1",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=1.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "*/* ;q=0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ;q=0.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ;q=0.5",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ;q=1",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ;q=1.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "*/*; q=0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*; q=0.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*; q=0.5",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*; q=1",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*; q=1.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "*/* ; q=0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ; q=0.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ; q=0.5",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ; q=1",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/* ; q=1.0",
+			Expected: mediarange.Create("*", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "*/*;q=0;once=1;twice=22;thrice=333;fource=4444",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=0.0;once=1;twice=22;thrice=333;fource=4444",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=0.5;once=1;twice=22;thrice=333;fource=4444",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=1;once=1;twice=22;thrice=333;fource=4444",
+			Expected: mediarange.Create("*", "*"),
+		},
+		{
+			MediaRange:                 "*/*;q=1.0;once=1;twice=22;thrice=333;fource=4444",
+			Expected: mediarange.Create("*", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "application/*",
+			Expected: mediarange.Create("application", "*"),
+		},
+		{
+			MediaRange:                 "audio/*",
+			Expected: mediarange.Create("audio", "*"),
+		},
+		{
+			MediaRange:                 "font/*",
+			Expected: mediarange.Create("font", "*"),
+		},
+		{
+			MediaRange:                 "image/*",
+			Expected: mediarange.Create("image", "*"),
+		},
+		{
+			MediaRange:                 "text/*",
+			Expected: mediarange.Create("text", "*"),
+		},
+		{
+			MediaRange:                 "video/*",
+			Expected: mediarange.Create("video", "*"),
+		},
+		{
+			MediaRange:                 "xyz/*",
+			Expected: mediarange.Create("xyz", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "Application/*",
+			Expected: mediarange.Create("application", "*"),
+		},
+		{
+			MediaRange:                 "audIO/*",
+			Expected: mediarange.Create("audio", "*"),
+		},
+		{
+			MediaRange:                 "FonT/*",
+			Expected: mediarange.Create("font", "*"),
+		},
+		{
+			MediaRange:                 "IMAGE/*",
+			Expected: mediarange.Create("image", "*"),
+		},
+		{
+			MediaRange:                 "tEXT/*",
+			Expected: mediarange.Create("text", "*"),
+		},
+		{
+			MediaRange:                 "vIDeo/*",
+			Expected: mediarange.Create("video", "*"),
+		},
+		{
+			MediaRange:                 "Xyz/*",
+			Expected: mediarange.Create("xyz", "*"),
+		},
+
+
+
+		{
+			MediaRange:                 "application/XHTML+XML",
+			Expected: mediarange.Create("application", "xhtml+xml"),
+		},
+		{
+			MediaRange:                 "IMAGE/png",
+			Expected: mediarange.Create("image", "png"),
+		},
+		{
+			MediaRange:                 "text/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "Text/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "TexT/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "tExt/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "teXt/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "texT/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "text/Html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "text/hTml",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "text/htMl",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "text/htmL",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "TeXT/HTml",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "TEXT/html",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "text/HTML",
+			Expected: mediarange.Create("text", "html"),
+		},
+		{
+			MediaRange:                 "TEXT/HTML",
+			Expected: mediarange.Create("text", "html"),
+		},
+	}
+
+	for testNumber, test := range tests {
+
+		actual, err := mediarange.Parse(test.MediaRange)
+		if nil != err {
+			t.Errorf("For test #%d, did not expect an error but actually got one.", testNumber)
+			t.Logf("MEDIA-RANGE: %q", test.MediaRange)
+			t.Logf("ERROR: (%T) %s", err, err)
+			continue
+		}
+
+		expected := test.Expected
+
+		if expected != actual {
+			t.Errorf("For tset #%d, the actual resulting media-range is not what was expected.", testNumber)
+			t.Logf("MEDIA-RANGE: %q", test.MediaRange)
+			t.Logf("EXPECTED: %q %#v", expected, expected)
+			t.Logf("ACTUAL:   %q %#v", actual, actual)
+			continue
+		}
+
+	}
+}
diff --git a/mediarange/mediarange_string_test.go b/mediarange/mediarange_string_test.go
new file mode 100644
index 0000000..f59d011
--- /dev/null
+++ b/mediarange/mediarange_string_test.go
@@ -0,0 +1,434 @@
+package mediarange_test
+
+import (
+	"sourcecode.social/reiver/go-httpaccept/mediarange"
+
+	"testing"
+)
+
+func TestMediaRange_String(t *testing.T) {
+
+	tests := []struct{
+		MediaRange mediarange.MediaRange
+		Expected string
+	}{
+		{
+			MediaRange: mediarange.Create("", ""),
+			Expected:                     "*"+"/"+"*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("*"  ,  "*"),
+			Expected:                     "*"+"/"+"*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  ""),
+			Expected:                     "application"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  ""),
+			Expected:                     "audio"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  ""),
+			Expected:                     "font"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  ""),
+			Expected:                     "image"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  ""),
+			Expected:                     "text"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  ""),
+			Expected:                     "video"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  ""),
+			Expected:                     "xyz"+"/"+"*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "*"),
+			Expected:                     "application"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "*"),
+			Expected:                     "audio"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  "*"),
+			Expected:                     "font"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "*"),
+			Expected:                     "image"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  ""),
+			Expected:                     "text"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  ""),
+			Expected:                     "video"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  ""),
+			Expected:                     "xyz"+"/"+"*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("Application"  ,  "*"),
+			Expected:                     "application"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("Audio"  ,  "*"),
+			Expected:                     "audio"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("Font"  ,  "*"),
+			Expected:                     "font"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("Image"  ,  "*"),
+			Expected:                     "image"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("Text"  ,  ""),
+			Expected:                     "text"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("Video"  ,  ""),
+			Expected:                     "video"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("Xyz"  ,  ""),
+			Expected:                     "xyz"+"/"+"*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("APPLICATION"  ,  "*"),
+			Expected:                     "application"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("AUDIO"  ,  "*"),
+			Expected:                     "audio"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("FONT"  ,  "*"),
+			Expected:                     "font"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("IMAGE"  ,  "*"),
+			Expected:                     "image"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("TEXT"  ,  ""),
+			Expected:                     "text"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("VIDEO"  ,  ""),
+			Expected:                     "video"+"/"+"*",
+		},
+		{
+			MediaRange: mediarange.Create("XYZ"  ,  ""),
+			Expected:                     "xyz"+"/"+"*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "activity+json"),
+			Expected:                     "application"+"/"+"activity+json",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "epub+zip"),
+			Expected:                     "application"+"/"+"epub+zip",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "gzip"),
+			Expected:                     "application"+"/"+"gzip",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "java-archive"),
+			Expected:                     "application"+"/"+"java-archive",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "json"),
+			Expected:                     "application"+"/"+"json",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "ld+json"),
+			Expected:                     "application"+"/"+"ld+json",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "pdf"),
+			Expected:                     "application"+"/"+"pdf",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "msword"),
+			Expected:                     "application"+"/"+"msword",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "octet-stream"),
+			Expected:                     "application"+"/"+"octet-stream",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "ogg"),
+			Expected:                     "application"+"/"+"ogg",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "rtf"),
+			Expected:                     "application"+"/"+"rtf",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.oasis.opendocument.spreadsheet"),
+			Expected:                     "application"+"/"+"vnd.oasis.opendocument.spreadsheet",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.openxmlformats-officedocument.wordprocessingml.document"),
+			Expected:                     "application"+"/"+"vnd.openxmlformats-officedocument.wordprocessingml.document",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.mozilla.xul+xml"),
+			Expected:                     "application"+"/"+"vnd.mozilla.xul+xml",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.ms-excel"),
+			Expected:                     "application"+"/"+"vnd.ms-excel",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-7z-compressed"),
+			Expected:                     "application"+"/"+"x-7z-compressed",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-bzip"),
+			Expected:                     "application"+"/"+"x-bzip",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-bzip2"),
+			Expected:                     "application"+"/"+"x-bzip2",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-cdf"),
+			Expected:                     "application"+"/"+"x-cdf",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-csh"),
+			Expected:                     "application"+"/"+"x-csh",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-freearc"),
+			Expected:                     "application"+"/"+"x-freearc",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-httpd-php"),
+			Expected:                     "application"+"/"+"x-httpd-php",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-sh"),
+			Expected:                     "application"+"/"+"x-sh",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-tar"),
+			Expected:                     "application"+"/"+"x-tar",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "xhtml+xml"),
+			Expected:                     "application"+"/"+"xhtml+xml",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("audio"  ,  "aac"),
+			Expected:                     "audio"+"/"+"aac",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "midi"),
+			Expected:                     "audio"+"/"+"midi",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "mpeg"),
+			Expected:                     "audio"+"/"+"mpeg",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "ogg"),
+			Expected:                     "audio"+"/"+"ogg",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "opus"),
+			Expected:                     "audio"+"/"+"opus",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "wav"),
+			Expected:                     "audio"+"/"+"wav",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "webm"),
+			Expected:                     "audio"+"/"+"webm",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "3gpp"),
+			Expected:                     "audio"+"/"+"3gpp",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "3gpp2"),
+			Expected:                     "audio"+"/"+"3gpp2",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "x-midi"),
+			Expected:                     "audio"+"/"+"x-midi",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("font"  ,  "ttf"),
+			Expected:                     "font"+"/"+"ttf",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("image"  ,  "avif"),
+			Expected:                     "image"+"/"+"avif",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "bmp"),
+			Expected:                     "image"+"/"+"bmp",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "gif"),
+			Expected:                     "image"+"/"+"gif",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "png"),
+			Expected:                     "image"+"/"+"png",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "tiff"),
+			Expected:                     "image"+"/"+"tiff",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("text"  ,  "css"),
+			Expected:                     "text"+"/"+"css",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "csv"),
+			Expected:                     "text"+"/"+"csv",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "html"),
+			Expected:                     "text"+"/"+"html",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "javascript"),
+			Expected:                     "text"+"/"+"javascript",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "markdown"),
+			Expected:                     "text"+"/"+"markdown",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "plain"),
+			Expected:                     "text"+"/"+"plain",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "x-markdown"),
+			Expected:                     "text"+"/"+"x-markdown",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("video"  ,  "3gpp2"),
+			Expected:                     "video"+"/"+"3gpp2",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "ogg"),
+			Expected:                     "video"+"/"+"ogg",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mp2t"),
+			Expected:                     "video"+"/"+"mp2t",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mp4"),
+			Expected:                     "video"+"/"+"mp4",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mpeg"),
+			Expected:                     "video"+"/"+"mpeg",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "webm"),
+			Expected:                     "video"+"/"+"webm",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "x-msvideo"),
+			Expected:                     "video"+"/"+"x-msvideo",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "ACTIVITY+JSON"),
+			Expected:                     "application"+"/"+"activity+json",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "MPEG"),
+			Expected:                     "audio"+"/"+"mpeg",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  "TTF"),
+			Expected:                     "font"+"/"+"ttf",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "PNG"),
+			Expected:                     "image"+"/"+"png",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "HTML"),
+			Expected:                     "text"+"/"+"html",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "OGG"),
+			Expected:                     "video"+"/"+"ogg",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  "BANANA"),
+			Expected:                     "xyz"+"/"+"banana",
+		},
+	}
+
+	for testNumber, test := range tests {
+
+		actual := test.MediaRange.String()
+		expected := test.Expected
+
+		if expected != actual {
+			t.Errorf("For test #%d, the actual (serialized) stringer value is not what was expected.", testNumber)
+			t.Logf("MEDIA-RANGE: %#v", test.MediaRange)
+			t.Logf("EXPECTED: %q", expected)
+			t.Logf("ACTUAL:   %q", actual)
+			continue
+		}
+	}
+}
diff --git a/mediarange/mediarange_subtype_test.go b/mediarange/mediarange_subtype_test.go
new file mode 100644
index 0000000..6e3224a
--- /dev/null
+++ b/mediarange/mediarange_subtype_test.go
@@ -0,0 +1,481 @@
+package mediarange_test
+
+import (
+	"sourcecode.social/reiver/go-httpaccept/mediarange"
+
+	"testing"
+)
+
+func TestMediaRange_SubType(t *testing.T) {
+
+	tests := []struct{
+		MediaRange mediarange.MediaRange
+		Expected string
+	}{
+		{
+			MediaRange: mediarange.Create(""  ,  ""),
+			Expected:                            "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("*"  ,  "*"),
+			Expected:                             "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  ""),
+			Expected:                                       "*",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  ""),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  ""),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  ""),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  ""),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  ""),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  ""),
+			Expected:                               "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "*"),
+			Expected:                                       "*",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "*"),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  "*"),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "*"),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  ""),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  ""),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  ""),
+			Expected:                               "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("Application"  ,  "*"),
+			Expected:                                       "*",
+		},
+		{
+			MediaRange: mediarange.Create("Audio"  ,  "*"),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("Font"  ,  "*"),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("Image"  ,  "*"),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("Text"  ,  ""),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("Video"  ,  ""),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("Xyz"  ,  ""),
+			Expected:                               "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("APPLICATION"  ,  "*"),
+			Expected:                                       "*",
+		},
+		{
+			MediaRange: mediarange.Create("AUDIO"  ,  "*"),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("FONT"  ,  "*"),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("IMAGE"  ,  "*"),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("TEXT"  ,  ""),
+			Expected:                                "*",
+		},
+		{
+			MediaRange: mediarange.Create("VIDEO"  ,  ""),
+			Expected:                                 "*",
+		},
+		{
+			MediaRange: mediarange.Create("XYZ"  ,  ""),
+			Expected:                               "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "activity+json"),
+			Expected:                                       "activity+json",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "epub+zip"),
+			Expected:                                       "epub+zip",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "gzip"),
+			Expected:                                       "gzip",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "java-archive"),
+			Expected:                                       "java-archive",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "json"),
+			Expected:                                       "json",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "ld+json"),
+			Expected:                                       "ld+json",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "pdf"),
+			Expected:                                       "pdf",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "msword"),
+			Expected:                                       "msword",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "octet-stream"),
+			Expected:                                       "octet-stream",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "ogg"),
+			Expected:                                       "ogg",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "rtf"),
+			Expected:                                       "rtf",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.oasis.opendocument.spreadsheet"),
+			Expected:                                       "vnd.oasis.opendocument.spreadsheet",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.openxmlformats-officedocument.wordprocessingml.document"),
+			Expected:                                       "vnd.openxmlformats-officedocument.wordprocessingml.document",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.mozilla.xul+xml"),
+			Expected:                                       "vnd.mozilla.xul+xml",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.ms-excel"),
+			Expected:                                       "vnd.ms-excel",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-7z-compressed"),
+			Expected:                                       "x-7z-compressed",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-bzip"),
+			Expected:                                       "x-bzip",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-bzip2"),
+			Expected:                                       "x-bzip2",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-cdf"),
+			Expected:                                       "x-cdf",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-csh"),
+			Expected:                                       "x-csh",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-freearc"),
+			Expected:                                       "x-freearc",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-httpd-php"),
+			Expected:                                       "x-httpd-php",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-sh"),
+			Expected:                                       "x-sh",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-tar"),
+			Expected:                                       "x-tar",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "xhtml+xml"),
+			Expected:                                       "xhtml+xml",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("audio"  ,  "aac"),
+			Expected:                                 "aac",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "midi"),
+			Expected:                                 "midi",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "mpeg"),
+			Expected:                                 "mpeg",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "ogg"),
+			Expected:                                 "ogg",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "opus"),
+			Expected:                                 "opus",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "wav"),
+			Expected:                                 "wav",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "webm"),
+			Expected:                                 "webm",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "3gpp"),
+			Expected:                                 "3gpp",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "3gpp2"),
+			Expected:                                 "3gpp2",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "x-midi"),
+			Expected:                                 "x-midi",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("font"  ,  "ttf"),
+			Expected:                                "ttf",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("image"  ,  "avif"),
+			Expected:                                 "avif",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "bmp"),
+			Expected:                                 "bmp",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "gif"),
+			Expected:                                 "gif",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "png"),
+			Expected:                                 "png",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "tiff"),
+			Expected:                                 "tiff",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("text"  ,  "css"),
+			Expected:                                "css",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "csv"),
+			Expected:                                "csv",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "html"),
+			Expected:                                "html",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "javascript"),
+			Expected:                                "javascript",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "markdown"),
+			Expected:                                "markdown",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "plain"),
+			Expected:                                "plain",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "x-markdown"),
+			Expected:                                "x-markdown",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("video"  ,  "3gpp2"),
+			Expected:                                 "3gpp2",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "ogg"),
+			Expected:                                 "ogg",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mp2t"),
+			Expected:                                 "mp2t",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mp4"),
+			Expected:                                 "mp4",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mpeg"),
+			Expected:                                 "mpeg",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "webm"),
+			Expected:                                 "webm",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "x-msvideo"),
+			Expected:                                 "x-msvideo",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "ACTIVITY+JSON"),
+			Expected:                                       "activity+json",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "MPEG"),
+			Expected:                                 "mpeg",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  "TTF"),
+			Expected:                                "ttf",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "PNG"),
+			Expected:                                 "png",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "HTML"),
+			Expected:                                "html",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "OGG"),
+			Expected:                                 "ogg",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  "BANANA"),
+			Expected:                               "banana",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("*"  ,  ""),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "apple"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "BANANA"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "Cherry"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "gif"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "html"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "javascript"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "json"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "png"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "webm"),
+			Expected:                             "*",
+		},
+		{
+			MediaRange: mediarange.Create("*"  ,  "xml"),
+			Expected:                             "*",
+		},
+	}
+
+	for testNumber, test := range tests {
+
+		actual := test.MediaRange.SubType()
+		expected := test.Expected
+
+		if expected != actual {
+			t.Errorf("For test #%d, the actual canonical-subtype is not what was expected.", testNumber)
+			t.Logf("MEDIA-RANGE: %#v", test.MediaRange)
+			t.Logf("EXPECTED: %q", expected)
+			t.Logf("ACTUAL:   %q", actual)
+			continue
+		}
+	}
+}
diff --git a/mediarange/mediarange_type_test.go b/mediarange/mediarange_type_test.go
new file mode 100644
index 0000000..b66e1b9
--- /dev/null
+++ b/mediarange/mediarange_type_test.go
@@ -0,0 +1,434 @@
+package mediarange_test
+
+import (
+	"sourcecode.social/reiver/go-httpaccept/mediarange"
+
+	"testing"
+)
+
+func TestMediaRange_Type(t *testing.T) {
+
+	tests := []struct{
+		MediaRange mediarange.MediaRange
+		Expected string
+	}{
+		{
+			MediaRange: mediarange.Create(""  ,  ""),
+			Expected:                     "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("*"  ,  "*"),
+			Expected:                     "*",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  ""),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  ""),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  ""),
+			Expected:                     "font",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  ""),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  ""),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  ""),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  ""),
+			Expected:                     "xyz",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "*"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "*"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  "*"),
+			Expected:                     "font",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "*"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  ""),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  ""),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  ""),
+			Expected:                     "xyz",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("Application"  ,  "*"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("Audio"  ,  "*"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("Font"  ,  "*"),
+			Expected:                     "font",
+		},
+		{
+			MediaRange: mediarange.Create("Image"  ,  "*"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("Text"  ,  ""),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("Video"  ,  ""),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("Xyz"  ,  ""),
+			Expected:                     "xyz",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("APPLICATION"  ,  "*"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("AUDIO"  ,  "*"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("FONT"  ,  "*"),
+			Expected:                     "font",
+		},
+		{
+			MediaRange: mediarange.Create("IMAGE"  ,  "*"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("TEXT"  ,  ""),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("VIDEO"  ,  ""),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("XYZ"  ,  ""),
+			Expected:                     "xyz",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "activity+json"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "epub+zip"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "gzip"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "java-archive"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "json"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "ld+json"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "pdf"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "msword"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "octet-stream"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "ogg"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "rtf"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.oasis.opendocument.spreadsheet"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.openxmlformats-officedocument.wordprocessingml.document"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.mozilla.xul+xml"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "vnd.ms-excel"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-7z-compressed"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-bzip"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-bzip2"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-cdf"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-csh"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-freearc"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-httpd-php"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-sh"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "x-tar"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("application"  ,  "xhtml+xml"),
+			Expected:                     "application",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("audio"  ,  "aac"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "midi"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "mpeg"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "ogg"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "opus"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "wav"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "webm"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "3gpp"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "3gpp2"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "x-midi"),
+			Expected:                     "audio",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("font"  ,  "ttf"),
+			Expected:                     "font",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("image"  ,  "avif"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "bmp"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "gif"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "png"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "tiff"),
+			Expected:                     "image",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("text"  ,  "css"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "csv"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "html"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "javascript"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "markdown"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "plain"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "x-markdown"),
+			Expected:                     "text",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("video"  ,  "3gpp2"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "ogg"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mp2t"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mp4"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "mpeg"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "webm"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "x-msvideo"),
+			Expected:                     "video",
+		},
+
+
+
+		{
+			MediaRange: mediarange.Create("application"  ,  "ACTIVITY+JSON"),
+			Expected:                     "application",
+		},
+		{
+			MediaRange: mediarange.Create("audio"  ,  "MPEG"),
+			Expected:                     "audio",
+		},
+		{
+			MediaRange: mediarange.Create("font"  ,  "TTF"),
+			Expected:                     "font",
+		},
+		{
+			MediaRange: mediarange.Create("image"  ,  "PNG"),
+			Expected:                     "image",
+		},
+		{
+			MediaRange: mediarange.Create("text"  ,  "HTML"),
+			Expected:                     "text",
+		},
+		{
+			MediaRange: mediarange.Create("video"  ,  "OGG"),
+			Expected:                     "video",
+		},
+		{
+			MediaRange: mediarange.Create("xyz"  ,  "BANANA"),
+			Expected:                     "xyz",
+		},
+	}
+
+	for testNumber, test := range tests {
+
+		actual := test.MediaRange.Type()
+		expected := test.Expected
+
+		if expected != actual {
+			t.Errorf("For test #%d, the actual canonical-type is not what was expected.", testNumber)
+			t.Logf("MEDIA-RANGEE: %#v", test.MediaRange)
+			t.Logf("EXPECTED: %q", expected)
+			t.Logf("ACTUAL:   %q", actual)
+			continue
+		}
+	}
+}