generic interface implementation. ready for generic update

buffer.go

@@ -1,12 +1,13 @@
 package buf2d
 
 import (
+	"fmt"
 	"strings"
 )
 
 // Buffer is a 2-dimensional rune buffer
 type Buffer struct {
-	data   [][]rune
+	data   [][]fmt.Stringer
 	width  int
 	height int
 	parent *Buffer
@@ -14,11 +15,11 @@ type Buffer struct {
 
 // NewBuffer makes a new buffer with the given dimensions
 func NewBuffer(width, height int) *Buffer {
-	b := make([][]rune, height)
+	b := make([][]fmt.Stringer, height)
 	for y := range b {
-		b[y] = make([]rune, width)
+		b[y] = make([]fmt.Stringer, width)
 		for x := range b[y] {
-			b[y][x] = ' '
+			b[y][x] = spaceStringer
 		}
 	}
 
@@ -38,13 +39,18 @@ func (b *Buffer) y(y int) int {
 	return limit(y, 0, b.height-1)
 }
 
-// Set sets the rune at position (x,y) to c
+// Set sets the fmt.Stringer at position (x,y) to c
-func (b *Buffer) Set(x, y int, c rune) {
+func (b *Buffer) Set(x, y int, c fmt.Stringer) {
 	b.data[b.y(y)][b.x(x)] = c
 }
 
-// Get returns the rune at position (x,y)
+// SetRune sets the fmt.Stringer at position (x,y) to rn
-func (b *Buffer) Get(x, y int) rune {
+func (b *Buffer) SetRune(x, y int, rn rune) {
+	b.data[b.y(y)][b.x(x)] = newStringerFromRune(rn)
+}
+
+// Get returns the fmt.Stringer at position (x,y)
+func (b *Buffer) Get(x, y int) fmt.Stringer {
 	return b.data[y][x]
 }
 
@@ -63,11 +69,11 @@ func (b *Buffer) Height() int {
 	return b.height
 }
 
-// Draw calls drawFunc for every rune in this buffer
+// ForEach calls f for every rune in this buffer
-func (b *Buffer) Draw(drawFunc func(x, y int, c rune)) {
+func (b *Buffer) ForEach(f func(x, y int, c fmt.Stringer)) {
 	for y, col := range b.data {
-		for x, char := range col {
+		for x, v := range col {
-			drawFunc(x, y, char)
+			f(x, y, v)
 		}
 	}
 }
@@ -75,8 +81,8 @@ func (b *Buffer) Draw(drawFunc func(x, y int, c rune)) {
 func (b *Buffer) String() string {
 	s := new(strings.Builder)
 	for ci, col := range b.data {
-		for _, char := range col {
+		for _, v := range col {
-			s.WriteRune(char)
+			s.WriteString(fmt.Sprintf("%v", v))
 		}
 		if ci != len(b.data)-1 {
 			s.WriteRune('\n')
@@ -97,7 +103,7 @@ func (b *Buffer) Sub(x, y, w, h int) *Buffer {
 	h = limit(h, 1, b.height-y)
 
 	// make slice references
-	data := make([][]rune, h)
+	data := make([][]fmt.Stringer, h)
 	for dy := 0; dy < h; dy++ {
 		col := b.data[y+dy]
 		data[dy] = col[x : x+w]

buffer_test.go

@@ -9,8 +9,8 @@ import (
 func TestSub(t *testing.T) {
 	b := NewBuffer(10, 10)
 	s := b.Sub(1, 1, b.Width()-1, b.Height()-1)
-	b.Set(5, 1, 'a')
+	b.SetRune(5, 1, 'a')
-	s.Set(5, 5, 'b')
+	s.SetRune(5, 5, 'b')
 	b.WriteString("Hello world", 1, 2)
 
 	fmt.Println(b)

utils.go

@@ -1,5 +1,7 @@
 package buf2d
 
+import "fmt"
+
 func limit(v, min, max int) int {
 	return getmax(getmin(v, max), min)
 }
@@ -17,3 +19,22 @@ func getmin(x, y int) int {
 	}
 	return y
 }
+
+type stringerImpl string
+
+func (s *stringerImpl) String() string {
+	return string(*s)
+}
+
+func newStringer(str string) fmt.Stringer {
+	var impl stringerImpl = stringerImpl(str)
+	return &impl
+}
+
+func newStringerFromRune(rn rune) fmt.Stringer {
+	return newStringer(string(rn))
+}
+
+var (
+	spaceStringer = newStringer(" ")
+)

write_string.go

@@ -1,6 +1,9 @@
 package buf2d
 
-import "strings"
+import (
+	"fmt"
+	"strings"
+)
 
 // WriteString writes a whole string to the buffer at position (x,y)
 // no word wrap is applied at all. If the string does not fit, it will be truncated
@@ -10,7 +13,7 @@ func (b *Buffer) WriteString(str string, x, y int) {
 		if dx >= b.width {
 			return
 		}
-		b.Set(dx, y, r)
+		b.Set(dx, y, newStringerFromRune(r))
 		dx++
 	}
 }
@@ -30,7 +33,7 @@ func (b *Buffer) WriteMultiLineString(str string, x, y int) {
 }
 
 // Fill fills the whole buffer with c
-func (b *Buffer) Fill(c rune) {
+func (b *Buffer) Fill(c fmt.Stringer) {
 	for _, col := range b.data {
 		for ri := range col {
 			col[ri] = c