ch4 done

ch4/ex4-5.raku

@@ -0,0 +1,14 @@
+sub MAIN (
+	$num1, #= Number to perform arithmatic on
+	$num2 #= Second number to perform arithmatic on
+) {
+	die "unexpected input" unless is-numeric($num1) and is-numeric($num2);
+	say "sum is {$num1 + $num2}";
+	say "difference is {$num1 - $num2}";
+	say "product is {$num1 * $num2}";
+	say "quotient is {$num1 / $num2}";
+}
+
+sub is-numeric ($num) {
+	return val($num) ~~ Numeric;
+}

ch4/ex4-6.raku

@@ -0,0 +1,5 @@
+sub MAIN (
+	$my-string #= String to count characters/display
+) {
+	say "$my-string has {$my-string.chars} characters";
+}

ch4/ex4-7.raku

@@ -0,0 +1,10 @@
+sub MAIN () {
+	# Unset PATH for shell safety (pg. 68)
+	%*ENV<PATH> = '';
+	print Q :x 'C:\Windows\System32\hostname.exe' if $*DISTRO.is-win;
+	print Q :x '/bin/hostname' unless $*DISTRO.is-win;
+
+	#avoid variable inputs for shell scripts
+	#qqx/date $my-new-date/
+	#my $my-new-date = '; /bin/rm -rf';
+}