Add modules

internal/editor/editor.go

@@ -0,0 +1 @@
+package editor

internal/rune/rune.go

@@ -0,0 +1,29 @@
+package rune
+
+func isAscii(char rune) bool {
+	ord := int(char)
+
+	return ord < 0x80
+}
+
+func IsCtrl(char rune) bool {
+	if !isAscii(char) {
+		return false
+	}
+
+	ord := int(char)
+
+	return ord == 0x7f || ord < 0x20
+}
+
+// Return the input code of a Ctrl-key chord.
+func Ctrl(char rune) rune {
+	ord := int(char)
+	raw := ord & 0x1f
+
+	if !IsCtrl(rune(raw)) {
+		return 0
+	}
+
+	return rune(raw)
+}

internal/terminal/terminal.go

@@ -0,0 +1,32 @@
+package terminal
+
+import (
+	"fmt"
+	"golang.org/x/term"
+	"os"
+)
+
+// Put the terminal in raw mode
+func RawOn() *term.State {
+	oldState, err := term.MakeRaw(int(os.Stdin.Fd()))
+	if err != nil {
+		panic(err)
+	}
+
+	return oldState
+}
+
+// Restore the terminal to canonical mode
+func RawOff(oldState *term.State) {
+	err := term.Restore(int(os.Stdin.Fd()), oldState)
+	if err != nil {
+		panic(err)
+	}
+}
+
+// Print a formatted string to stdout, with CRLF line endings for proper terminal formatting
+func OutLn(format string, a ...interface{}) {
+	formatted := fmt.Sprintf(format, a...)
+
+	fmt.Printf("%s\r\n", formatted)
+}