Merge branch 'master' of https://github.com/leafo/moonscript into compile_for_lua5.3

bin/moonc

@@ -314,16 +314,22 @@ if opts.w then
 
 	io.stderr:write("\nQuitting...\n")
 elseif opts.l then
+	local has_linted_with_error;
 	local lint = require "moonscript.cmd.lint"
 	for _, tuple in pairs(files) do
 		local fname = tuple[1]
 		local res, err = lint.lint_file(fname)
 		if res then
+			has_linted_with_error = true
 			io.stderr:write(res .. "\n\n")
 		elseif err then
+			has_linted_with_error = true
 			io.stderr:write(fname .. "\n" .. err.. "\n\n")
 		end
 	end
+	if has_linted_with_error then
+		os.exit(1)
+	end
 else
 	for _, tuple in ipairs(files) do
 		local fname, target = util.unpack(tuple)

docs/command_line.md

@@ -134,11 +134,14 @@ A full list of flags can be seen by passing the `-h` or `--help` flag.
 
 `moonc` contains a [lint][1] tool for statically detecting potential problems
 with code. The linter has two tests: detects accessed global variables,
-detect unused declared variables.
+detect unused declared variables. If the linter detects any issues with a file,
+the program will exit with a status of `1`.
 
 You can execute the linter with the `-l` flag. When the linting flag is
 provided only linting takes place and no compiled code is generated.
 
+The linter is compatible with the watch mode (see above) for automatic linting.
+
 ```bash
 moonc -l file1.moon file2.moon
 ```