Синтаксический сахар (= вместо return) для коротких функций

Author: aNNiMON

program.own

@@ -64,18 +64,18 @@ print "\n\n"
 array = newarray(2, 2, 2, 2)
 print array
 
-add = def(a,b) return a+b
-sub = def(a,b) return a-b
-mul = def(a,b) return a*b
-div = def(a,b) return a/b
-cube = def(x) return x*mul(x, x)
+add = def(a,b) = a+b
+sub = def(a,b) = a-b
+mul = def(a,b) = a*b
+div = def(a,b) = a/b
+cube = def(x) = x*mul(x, x)
 print "\n\n"
 print mul(8, 5)
 print "\n"
 print cube(2)
 
 functions = [add, sub, mul, div]
-def function(f, a, b) return f(a, b)
+def function(f, a, b) = f(a, b)
 for i = 0, i < 4, i = i + 1 {
     print "\n"
     print functions[i]

src/com/annimon/ownlang/parser/Parser.java

@@ -141,6 +141,10 @@ private FunctionDefineStatement functionDefine() {
             argNames.add(consume(TokenType.WORD).getText());
             match(TokenType.COMMA);
         }
+        if (lookMatch(0, TokenType.EQ)) {
+            match(TokenType.EQ);
+            return new FunctionDefineStatement(name, argNames, new ReturnStatement(expression()));
+        }
         final Statement body = statementOrBlock();
         return new FunctionDefineStatement(name, argNames, body);
     }
@@ -411,8 +415,14 @@ private Expression primary() {
                 argNames.add(consume(TokenType.WORD).getText());
                 match(TokenType.COMMA);
             }
-            final Statement body = statementOrBlock();
-            return new ValueExpression(new UserDefinedFunction(argNames, body));
+            Statement statement;
+            if (lookMatch(0, TokenType.EQ)) {
+                match(TokenType.EQ);
+                statement = new ReturnStatement(expression());
+            } else {
+                statement = statementOrBlock();
+            }
+            return new ValueExpression(new UserDefinedFunction(argNames, statement));
         }
         if (match(TokenType.LPAREN)) {
             Expression result = expression();