.local/bin/e: Add working version, inspired by vipe

1 files changed, 79 insertions, 0 deletions

diff --git a/.local/bin/e b/.local/bin/e
new file mode 100755
index 0000000..76b4899
--- /dev/null
+++ b/.local/bin/e
@@ -0,0 +1,79 @@
+#!/bin/sh
+set -eu
+
+usage() {
+	cat <<-'EOF'
+		Usage:
+		  e [FILE]
+		  e -h
+	EOF
+}
+
+help() {
+	cat <<-'EOF'
+
+		Options:
+		  -h, --help
+
+
+		Flexibly run a text editor, either directly on in a pipe.
+
+		Examples:
+
+		  Edit "file.txt":
+
+		    $ e file.txt
+
+		  Manipulate the content of a pipe midway:
+
+		    $ seq 10 | e | grep 5
+
+		The editor used is either $VISUAL or $EDITOR, with a fallback to
+		vi in case any of those variables aren't defined.
+	EOF
+}
+
+for flag in "$@"; do
+	case "$flag" in
+		--)
+			break
+			;;
+		--help)
+			usage
+			help
+			exit
+			;;
+		*)
+			;;
+	esac
+done
+
+while getopts 'h' flag; do
+	case "$flag" in
+		h)
+			usage
+			help
+			exit
+			;;
+		*)
+			usage >&2
+			exit 2
+			;;
+	esac
+done
+shift $((OPTIND - 1))
+
+
+CMD="${VISUAL:-${EDITOR:-vi}}"
+
+if [ ! -t 0 ]; then
+	F="$(mkstemp)"
+	cat > "$F"
+	exec 0</dev/tty
+	exec 3>&1
+	exec 1>/dev/tty
+	$CMD "$F"
+	cat "$F" >&3
+else
+	$CMD "$@"
+fi