add bitwise update assignment operators (#277)

Author: Kawahara Satoru

moonscript/parse.lua

@@ -146,7 +146,7 @@ local build_grammar = wrap_env(debug_grammar, function(root)
     CompFor = key("for" * Name * sym("=") * Ct(Exp * sym(",") * Exp * (sym(",") * Exp) ^ -1) / mark("for")),
     CompClause = CompFor + CompForEach + key("when") * Exp / mark("when"),
     Assign = sym("=") * (Ct(With + If + Switch) + Ct(TableBlock + ExpListLow)) / mark("assign"),
-    Update = ((sym("..=") + sym("+=") + sym("-=") + sym("*=") + sym("/=") + sym("%=") + sym("or=") + sym("and=")) / trim) * Exp / mark("update"),
+    Update = ((sym("..=") + sym("+=") + sym("-=") + sym("*=") + sym("/=") + sym("%=") + sym("or=") + sym("and=") + sym("&=") + sym("|=") + sym(">>=") + sym("<<=")) / trim) * Exp / mark("update"),
     CharOperators = Space * C(S("+-*/%^><|&")),
     WordOperators = op("or") + op("and") + op("<=") + op(">=") + op("~=") + op("!=") + op("==") + op("..") + op("<<") + op(">>") + op("//"),
     BinaryOperator = (WordOperators + CharOperators) * SpaceBreak ^ 0,

moonscript/parse.moon

@@ -175,7 +175,7 @@ build_grammar = wrap_env debug_grammar, (root) ->
     CompClause: CompFor + CompForEach + key"when" * Exp / mark"when"
 
     Assign: sym"=" * (Ct(With + If + Switch) + Ct(TableBlock + ExpListLow)) / mark"assign"
-    Update: ((sym"..=" + sym"+=" + sym"-=" + sym"*=" + sym"/=" + sym"%=" + sym"or=" + sym"and=") / trim) * Exp / mark"update"
+    Update: ((sym"..=" + sym"+=" + sym"-=" + sym"*=" + sym"/=" + sym"%=" + sym"or=" + sym"and=" + sym"&=" + sym"|=" + sym">>=" + sym"<<=") / trim) * Exp / mark"update"
 
     CharOperators: Space * C(S"+-*/%^><|&")
     WordOperators: op"or" + op"and" + op"<=" + op">=" + op"~=" + op"!=" + op"==" + op".." + op"<<" + op">>" + op"//"

spec/inputs/syntax.moon

@@ -243,6 +243,8 @@ another hello, one,
 a += 3 - 5
 a *= 3 + 5
 a *= 3
+a >>= 3
+a <<= 3
 a /= func "cool"
 
 ---

spec/outputs/syntax.lua

@@ -241,6 +241,8 @@ another(hello, one, two, three, four, {
 a = a + (3 - 5)
 a = a * (3 + 5)
 a = a * 3
+a = a >> 3
+a = a << 3
 a = a / func("cool")
 x["then"] = "hello"
 x["while"]["true"] = "hello"