diff --git a/bidi/gen.go b/bidi/gen.go
index 8bdcb17..74bf76b 100644
--- a/bidi/gen.go
+++ b/bidi/gen.go
@@ -72,7 +72,7 @@
 	xorMap := map[rune]int{}
 	xorMasks := []rune{0} // First value is no-op.
 
-	parse("BidiBrackets.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("BidiBrackets.txt"), func(p *ucd.Parser) {
 		r1 := p.Rune(0)
 		r2 := p.Rune(1)
 		xor := r1 ^ r2
@@ -106,7 +106,7 @@
 	}
 
 	// Insert the derived BiDi properties.
-	parse("extracted/DerivedBidiClass.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("extracted/DerivedBidiClass.txt"), func(p *ucd.Parser) {
 		r := p.Rune(0)
 		class, ok := bidiClass[p.String(1)]
 		if !ok {
diff --git a/bidi/gen_ranges.go b/bidi/gen_ranges.go
index a0e6a04..9f4c335 100644
--- a/bidi/gen_ranges.go
+++ b/bidi/gen_ranges.go
@@ -7,7 +7,6 @@
 package main
 
 import (
-	"log"
 	"unicode"
 
 	"golang.org/x/text/internal/gen"
@@ -41,7 +40,7 @@
 	rangetable.Visit(unicode.Noncharacter_Code_Point, func(r rune) {
 		fn(r, _BN) // Boundary Neutral
 	})
-	parse("DerivedCoreProperties.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("DerivedCoreProperties.txt"), func(p *ucd.Parser) {
 		if p.String(1) == "Default_Ignorable_Code_Point" {
 			fn(p.Rune(0), _BN) // Boundary Neutral
 		}
@@ -56,17 +55,3 @@
 		}
 	}
 }
-
-// parse calls f for each entry in the given UCD file.
-func parse(filename string, f func(p *ucd.Parser)) {
-	r := gen.OpenUCDFile(filename)
-	defer r.Close()
-
-	p := ucd.New(r)
-	for p.Next() {
-		f(p)
-	}
-	if err := p.Err(); err != nil {
-		log.Fatal(err)
-	}
-}
diff --git a/bidi/ranges_test.go b/bidi/ranges_test.go
index a4ba376..dadbe95 100644
--- a/bidi/ranges_test.go
+++ b/bidi/ranges_test.go
@@ -3,7 +3,6 @@
 package bidi
 
 import (
-	"log"
 	"unicode"
 
 	"golang.org/x/text/internal/gen"
@@ -37,7 +36,7 @@
 	rangetable.Visit(unicode.Noncharacter_Code_Point, func(r rune) {
 		fn(r, _BN) // Boundary Neutral
 	})
-	parse("DerivedCoreProperties.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("DerivedCoreProperties.txt"), func(p *ucd.Parser) {
 		if p.String(1) == "Default_Ignorable_Code_Point" {
 			fn(p.Rune(0), _BN) // Boundary Neutral
 		}
@@ -52,17 +51,3 @@
 		}
 	}
 }
-
-// parse calls f for each entry in the given UCD file.
-func parse(filename string, f func(p *ucd.Parser)) {
-	r := gen.OpenUCDFile(filename)
-	defer r.Close()
-
-	p := ucd.New(r)
-	for p.Next() {
-		f(p)
-	}
-	if err := p.Err(); err != nil {
-		log.Fatal(err)
-	}
-}
diff --git a/bidi/tables_test.go b/bidi/tables_test.go
index 10d17ba..b2ad39b 100644
--- a/bidi/tables_test.go
+++ b/bidi/tables_test.go
@@ -51,7 +51,7 @@
 
 	trie := newBidiTrie(0)
 
-	parse("BidiBrackets.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("BidiBrackets.txt"), func(p *ucd.Parser) {
 		r1 := p.Rune(0)
 		want := p.Rune(1)
 
@@ -71,7 +71,7 @@
 	}
 
 	// Insert the derived BiDi properties.
-	parse("extracted/DerivedBidiClass.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("extracted/DerivedBidiClass.txt"), func(p *ucd.Parser) {
 		r := p.Rune(0)
 		test("derived", r, p.String(1))
 	})
diff --git a/cases/gen.go b/cases/gen.go
index fcc2633..1b6fdf5 100644
--- a/cases/gen.go
+++ b/cases/gen.go
@@ -90,22 +90,8 @@
 	return string(r.Rune)
 }
 
-// ucdParser is a parser for UCD files.
-type ucdParser []ucd.Option
-
-func parser(opts ...ucd.Option) ucdParser { return ucdParser(opts) }
-
-// parse calls f for each entry in the given UCD file.
-func (opts ucdParser) parse(filename string, f func(p *ucd.Parser)) {
-	r := gen.OpenUCDFile(filename)
-	defer r.Close()
-	p := ucd.New(r, opts...)
-	for p.Next() {
-		f(p)
-	}
-	if err := p.Err(); err != nil {
-		log.Fatal(err)
-	}
+func parse(file string, f func(p *ucd.Parser)) {
+	ucd.Parse(gen.OpenUCDFile(file), f)
 }
 
 func parseUCD() []runeInfo {
@@ -117,7 +103,7 @@
 		return c
 	}
 
-	parser().parse("UnicodeData.txt", func(p *ucd.Parser) {
+	parse("UnicodeData.txt", func(p *ucd.Parser) {
 		ri := get(p.Rune(0))
 		ri.CCC = byte(p.Int(ucd.CanonicalCombiningClass))
 		ri.Simple[cLower] = p.Runes(ucd.SimpleLowercaseMapping)
@@ -129,14 +115,14 @@
 	})
 
 	// <code>; <property>
-	parser().parse("PropList.txt", func(p *ucd.Parser) {
+	parse("PropList.txt", func(p *ucd.Parser) {
 		if p.String(1) == "Soft_Dotted" {
 			chars[p.Rune(0)].SoftDotted = true
 		}
 	})
 
 	// <code>; <word break type>
-	parser().parse("DerivedCoreProperties.txt", func(p *ucd.Parser) {
+	parse("DerivedCoreProperties.txt", func(p *ucd.Parser) {
 		ri := get(p.Rune(0))
 		switch p.String(1) {
 		case "Case_Ignorable":
@@ -151,7 +137,7 @@
 	})
 
 	// <code>; <lower> ; <title> ; <upper> ; (<condition_list> ;)?
-	parser().parse("SpecialCasing.txt", func(p *ucd.Parser) {
+	parse("SpecialCasing.txt", func(p *ucd.Parser) {
 		// We drop all conditional special casing and deal with them manually in
 		// the language-specific case mappers. Rune 0x03A3 is the only one with
 		// a conditional formatting that is not language-specific. However,
@@ -170,7 +156,7 @@
 
 	// TODO: Use text breaking according to UAX #29.
 	// <code>; <word break type>
-	parser().parse("auxiliary/WordBreakProperty.txt", func(p *ucd.Parser) {
+	parse("auxiliary/WordBreakProperty.txt", func(p *ucd.Parser) {
 		ri := get(p.Rune(0))
 		ri.BreakType = p.String(1)
 
@@ -185,7 +171,7 @@
 
 	// TODO: Support case folding.
 	// // <code>; <status>; <mapping>;
-	// parser().parse("CaseFolding.txt", func (p *ucd.Parser) {
+	// parse("CaseFolding.txt", func (p *ucd.Parser) {
 	// 	ri := get(p.Rune(0))
 	// 	switch p.String(1) {
 	// 	case "C":
@@ -647,7 +633,7 @@
 
 	// <code>; <lower> ; <title> ; <upper> ; (<condition_list> ;)?
 	fmt.Fprintln(w, "\tspecial = map[rune]struct{ toLower, toTitle, toUpper string }{")
-	parser().parse("SpecialCasing.txt", func(p *ucd.Parser) {
+	parse("SpecialCasing.txt", func(p *ucd.Parser) {
 		// Skip conditional entries.
 		if p.String(4) != "" {
 			return
@@ -660,7 +646,7 @@
 
 	// Break property
 	notBreak := map[rune]bool{}
-	parser().parse("auxiliary/WordBreakProperty.txt", func(p *ucd.Parser) {
+	parse("auxiliary/WordBreakProperty.txt", func(p *ucd.Parser) {
 		switch p.String(1) {
 		case "Extend", "Format", "MidLetter", "MidNumLet", "Single_Quote",
 			"ALetter", "Hebrew_Letter", "Numeric", "ExtendNumLet":
@@ -688,14 +674,14 @@
 	// Word break test
 	// Filter out all samples that do not contain cased characters.
 	cased := map[rune]bool{}
-	parser().parse("DerivedCoreProperties.txt", func(p *ucd.Parser) {
+	parse("DerivedCoreProperties.txt", func(p *ucd.Parser) {
 		if p.String(1) == "Cased" {
 			cased[p.Rune(0)] = true
 		}
 	})
 
 	fmt.Fprintln(w, "\tbreakTest = []string{")
-	parser(ucd.KeepRanges).parse("auxiliary/WordBreakTest.txt", func(p *ucd.Parser) {
+	parse("auxiliary/WordBreakTest.txt", func(p *ucd.Parser) {
 		c := strings.Split(p.String(0), " ")
 
 		const sep = '|'
@@ -771,7 +757,7 @@
 	varNameParts := strings.Split(property, "_")
 	varNameParts[0] = strings.ToLower(varNameParts[0])
 	fmt.Fprintf(w, "\t%s = map[rune]bool{\n", strings.Join(varNameParts, ""))
-	parser().parse(file, func(p *ucd.Parser) {
+	parse(file, func(p *ucd.Parser) {
 		if p.String(1) == property {
 			r := p.Rune(0)
 			verify[r] = true
diff --git a/internal/ucd/ucd.go b/internal/ucd/ucd.go
index da2ffa5..2b0d1a1 100644
--- a/internal/ucd/ucd.go
+++ b/internal/ucd/ucd.go
@@ -15,6 +15,7 @@
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"regexp"
 	"strconv"
 	"strings"
@@ -39,6 +40,23 @@
 	SimpleTitlecaseMapping
 )
 
+// Parse calls f for each entry in the given reader of a UCD file. It will close
+// the reader upon return. It will call log.Fatal if any error occurred.
+//
+// This implements the most common usage pattern of using Parser.
+func Parse(r io.ReadCloser, f func(p *Parser)) {
+	defer r.Close()
+
+	p := New(r)
+	for p.Next() {
+		f(p)
+	}
+	if err := p.Err(); err != nil {
+		r.Close() // os.Exit will cause defers not to be called.
+		log.Fatal(err)
+	}
+}
+
 // An Option is used to configure a Parser.
 type Option func(p *Parser)
 
diff --git a/unicode/rangetable/gen.go b/unicode/rangetable/gen.go
index a6ea172..bea49dd 100644
--- a/unicode/rangetable/gen.go
+++ b/unicode/rangetable/gen.go
@@ -74,7 +74,8 @@
 	for _, v := range versions {
 		assigned := []rune{}
 
-		parse(v, func(p *ucd.Parser) {
+		r := gen.Open("http://www.unicode.org/Public/", "", v+"/ucd/UnicodeData.txt")
+		ucd.Parse(r, func(p *ucd.Parser) {
 			assigned = append(assigned, p.Rune(0))
 		})
 
@@ -95,20 +96,6 @@
 	gen.WriteGoFile("tables.go", "rangetable", w.Bytes())
 }
 
-// parse calls f for each entry in the given UCD file.
-func parse(version string, f func(p *ucd.Parser)) {
-	r := gen.Open("http://www.unicode.org/Public/", "", version+"/ucd/UnicodeData.txt")
-	defer r.Close()
-
-	p := ucd.New(r)
-	for p.Next() {
-		f(p)
-	}
-	if err := p.Err(); err != nil {
-		log.Fatal(err)
-	}
-}
-
 func print(w io.Writer, rt *unicode.RangeTable) {
 	fmt.Fprintln(w, "&unicode.RangeTable{")
 	fmt.Fprintln(w, "\tR16: []unicode.Range16{")
diff --git a/width/common_test.go b/width/common_test.go
index 0959b66..fb5545e 100644
--- a/width/common_test.go
+++ b/width/common_test.go
@@ -56,7 +56,7 @@
 	// We cannot reuse package norm's decomposition, as we need an unexpanded
 	// decomposition. We make use of the opportunity to verify that the
 	// decomposition type is as expected.
-	parse("UnicodeData.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("UnicodeData.txt"), func(p *ucd.Parser) {
 		r := p.Rune(0)
 		s := strings.SplitN(p.String(ucd.DecompMapping), " ", 2)
 		if !maps[s[0]] {
@@ -74,7 +74,7 @@
 	})
 
 	// <rune range>;<type>
-	parse("EastAsianWidth.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("EastAsianWidth.txt"), func(p *ucd.Parser) {
 		tag, ok := typeMap[p.String(1)]
 		if !ok {
 			log.Fatalf("Unknown width type %q", p.String(1))
@@ -90,17 +90,3 @@
 		f(r, tag, alt)
 	})
 }
-
-// parse calls f for each entry in the given UCD file.
-func parse(filename string, f func(p *ucd.Parser)) {
-	r := gen.OpenUCDFile(filename)
-	defer r.Close()
-
-	p := ucd.New(r)
-	for p.Next() {
-		f(p)
-	}
-	if err := p.Err(); err != nil {
-		log.Fatal(err)
-	}
-}
diff --git a/width/gen_common.go b/width/gen_common.go
index 813792c..601e752 100644
--- a/width/gen_common.go
+++ b/width/gen_common.go
@@ -60,7 +60,7 @@
 	// We cannot reuse package norm's decomposition, as we need an unexpanded
 	// decomposition. We make use of the opportunity to verify that the
 	// decomposition type is as expected.
-	parse("UnicodeData.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("UnicodeData.txt"), func(p *ucd.Parser) {
 		r := p.Rune(0)
 		s := strings.SplitN(p.String(ucd.DecompMapping), " ", 2)
 		if !maps[s[0]] {
@@ -78,7 +78,7 @@
 	})
 
 	// <rune range>;<type>
-	parse("EastAsianWidth.txt", func(p *ucd.Parser) {
+	ucd.Parse(gen.OpenUCDFile("EastAsianWidth.txt"), func(p *ucd.Parser) {
 		tag, ok := typeMap[p.String(1)]
 		if !ok {
 			log.Fatalf("Unknown width type %q", p.String(1))
@@ -94,17 +94,3 @@
 		f(r, tag, alt)
 	})
 }
-
-// parse calls f for each entry in the given UCD file.
-func parse(filename string, f func(p *ucd.Parser)) {
-	r := gen.OpenUCDFile(filename)
-	defer r.Close()
-
-	p := ucd.New(r)
-	for p.Next() {
-		f(p)
-	}
-	if err := p.Err(); err != nil {
-		log.Fatal(err)
-	}
-}