go version 1.19

go.mod

@@ -1,6 +1,6 @@
 module github.com/twpayne/go-shapefile
 
-go 1.21
+go 1.19
 
 require (
 	github.com/stretchr/testify v1.8.1
@@ -12,5 +12,6 @@ require (
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/exp v0.0.0-20240103183307-be819d1f06fc // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -12,6 +12,8 @@ github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKs
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/twpayne/go-geom v1.4.4 h1:bcCPAvvNSzjmpUqR0Uqh39ClCKtPx6kZVR7EakQaVJI=
 github.com/twpayne/go-geom v1.4.4/go.mod h1:Kz4sX4LtdesDQgkhsMERazLlH/NiCg90s6FPaNr0KNI=
+golang.org/x/exp v0.0.0-20240103183307-be819d1f06fc h1:ao2WRsKSzW6KuUY9IWPwWahcHCgR0s52IfwutMfEbdM=
+golang.org/x/exp v0.0.0-20240103183307-be819d1f06fc/go.mod h1:iRJReGqOEeBhDZGkGbynYwcHlctCvnjTYIamk7uXpHI=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b h1:PxfKdU9lEEDYjdIzOtC4qFWgkU2rGHdKlKowJSMN9h0=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
 golang.org/x/text v0.4.0 h1:BrVqGRd7+k1DiOgtnFvAkoQEWQvBc25ouMJM6429SFg=

scanner.go

@@ -16,11 +16,22 @@ import (
 	"strings"
 	"sync"
 
+	"golang.org/x/exp/constraints"
 	"golang.org/x/net/html/charset"
 	"golang.org/x/text/encoding"
 	"golang.org/x/text/encoding/charmap"
 )
 
+func max[T constraints.Ordered](x T, y ...T) T { //nolint: ireturn
+	a := x
+	for _, b := range y {
+		if a < b {
+			a = b
+		}
+	}
+	return a
+}
+
 // bufioReadCloser ...
 type bufioReadCloser = struct {
 	*bufio.Reader