🚧 save wip

Author: Nikolaus Piccolotto

.babelrc

@@ -4,6 +4,7 @@
   ],
   "plugins": [
     "transform-es2015-spread",
-    "transform-object-entries"
+    "transform-object-entries",
+    "transform-object-rest-spread"
   ]
 }

.eslintrc.json

@@ -4,6 +4,7 @@
     "node": true
   },
   "extends": "eslint:recommended",
+  "parser": "babel-eslint",
   "parserOptions": {
     "sourceType": "module"
   },

lib/regex.js

@@ -74,7 +74,6 @@ function catDeriv(regex, x) {
         })
       )
     );
-  } else {
   }
 
   return palt({
@@ -119,14 +118,16 @@ export function deriv(regex, x) {
     case cat:
       return catDeriv(regex, x);
   }
-  throw new Error(`Cannot derive unknown operation "${symbolToString(op)}"`);
+  throw new Error(
+    `Cannot derive unknown operation "${symbolToString(regex.op)}"`
+  );
 }
 
 function getReturn(regex) {
   switch (regex.op) {
     case cat:
       const catProcessed = regex.ret.reduce(
-        (agg, val) => Object.assign(agg, val),
+        (agg, val) => ({ ...agg, ...val }),
         {}
       );
       // unprocessed values
@@ -305,10 +306,14 @@ function palt(opts = {}) {
     ks,
     ret
   };
+  console.log(JSON.stringify(ps, null, 2));
   // if any of the alternatives is accepted, return that
   const acceptIdx = ps.findIndex(p => accepted(p));
   if (acceptIdx !== -1) {
     if (ks[acceptIdx]) {
+      console.log(acceptIdx, {
+        [ks[acceptIdx]]: ps[acceptIdx].ret
+      });
       return accept({
         [ks[acceptIdx]]: ps[acceptIdx].ret
       });
@@ -370,7 +375,7 @@ export function maybeImpl(name, predicate) {
     throw new Error(`Must provide a predicate to maybe.`);
   }
   return palt({
-    ps: [predicate, p.nil],
+    ps: [p.nil, predicate],
     ks: [name, name]
   });
 }

package.json

@@ -28,15 +28,17 @@
   "devDependencies": {
     "babel-cli": "^6.18.0",
     "babel-core": "^6.18.2",
+    "babel-eslint": "7",
     "babel-istanbul": "^0.11.0",
     "babel-loader": "^6.2.7",
     "babel-plugin-transform-es2015-spread": "^6.8.0",
     "babel-plugin-transform-object-entries": "^1.0.0",
+    "babel-plugin-transform-object-rest-spread": "^6.23.0",
     "babel-preset-es2015": "^6.18.0",
     "babel-register": "^6.18.0",
     "chai": "^3.5.0",
     "coveralls": "^2.11.14",
-    "eslint": "^4.4.1",
+    "eslint": "3.x",
     "eslint-plugin-prettier": "^2.1.2",
     "mocha": "^3.1.2",
     "nodemon": "^1.11.0",

test/regex/alt.test.js

@@ -84,23 +84,21 @@ describe("alt", () => {
 
     it("works with null/undefined", () => {
       // expect not nullable spec to be invalid for nil
-      expect(conform(ingredient_part, [])).to.deep.equal(invalid)
-      expect(conform(ingredient_part)).to.deep.equal(invalid)
+      expect(conform(ingredient_part, [])).to.deep.equal(invalid);
+      expect(conform(ingredient_part)).to.deep.equal(invalid);
 
       // expect nullable spec to be valid for nil
-      const nullable_alt = alt("value", p.number, "no value", p.nil)
+      const nullable_alt = alt("value", p.number, "no value", p.nil);
       expect(conform(nullable_alt, null)).to.deep.equal({
         "no value": null
-      })
+      });
       expect(conform(nullable_alt)).to.deep.equal({
         "no value": null
-      })
+      });
       expect(conform(nullable_alt, 5)).to.deep.equal({
-        "value": 5
-      })
-
-
-    })
+        value: 5
+      });
+    });
 
     it("works in happy nested case", () => {
       expect(