langs a-z

Task/Extend-your-language/UNIX-Shell/extend-your-language-1.sh

@@ -0,0 +1,7 @@
+if2() {
+	if eval "$1"; then
+		if eval "$2"; then eval "$3"; else eval "$4"; fi
+	else
+		if eval "$2"; then eval "$5"; else eval "$6"; fi
+	fi
+}

Task/Extend-your-language/UNIX-Shell/extend-your-language-2.sh

@@ -0,0 +1,9 @@
+if2 'test 7 -lt 9' 'test 7 -gt 9' '
+	echo both 1 and 2
+' '
+	echo 1 but not 2
+' '
+	echo 2 but not 1
+' '
+	echo neither 1 nor 2
+'

Task/Extend-your-language/UNIX-Shell/extend-your-language-3.sh

@@ -0,0 +1,9 @@
+fn if2 cond1 cond2 body11 body10 body01 body00 {
+	# Must evaluate both conditions, and should do so in order.
+	# Negation ensures a boolean result: a true condition becomes
+        # 1 for false; a false condition becomes 0 for true.
+	let (c1 = <={! $cond1}; c2 = <={! $cond2}) {
+		# Use those values to pick the body to evaluate.
+		$(body$c1$c2)
+	}
+}

Task/Extend-your-language/UNIX-Shell/extend-your-language-4.sh

@@ -0,0 +1,9 @@
+if2 {test 1 -gt 0} {~ grill foo bar boo} {
+	echo 1 and 2
+} {
+	echo 1 but not 2
+} {
+	echo 2 but not 1
+} {
+	echo neither 1 nor 2
+}