add ds-function to calculate dir sizes and sort them

init.fish

@@ -0,0 +1,27 @@
+function df --description 'df should always be human readable'
+    command df -h $argv
+end
+
+function ds --description 'calculate size of current or a given dir and sort by size'
+	switch (count $argv)
+
+		case 0
+		    du -hsx * .[a-zA-Z0-9_]* 2> /dev/null | \
+		    egrep '^ *[0-9.]*[MG]' | sort -n > /tmp/list
+		    egrep '^ *[0-9.]*M' /tmp/list
+		    egrep '^ *[0-9.]*G' /tmp/list
+		    rm -rf /tmp/list
+
+		case 1
+		    du -hx $argv .[a-zA-Z0-9_]* 2> /dev/null | \
+		    egrep '^ *[0-9.]*[MG]' | sort -n > /tmp/list
+		    egrep '^ *[0-9.]*M' /tmp/list
+		    egrep '^ *[0-9.]*G' /tmp/list
+		    rm -rf /tmp/list
+
+		case \*
+			echo "Only none or 1 argument is valid!"
+			return 1
+
+	end
+end