feat: expose ap as internal util

Our version of  only wraps original version of  and
adds backward compatibility layer with older versions of Monet
(and possibly other monadic libraries)

Closes #64

src/internal/ap.js

@@ -0,0 +1,28 @@
+import fl from 'fantasy-land';
+import { ap as apR, curryN, pathSatisfies, both, anyPass } from 'ramda';
+
+import isFunction from '../isFunction';
+
+
+const isFunctor = anyPass([pathSatisfies(isFunction, ['map']), pathSatisfies(isFunction, [fl.map])]);
+const isApply = both(
+  isFunctor,
+  anyPass([pathSatisfies(isFunction, ['ap']), pathSatisfies(isFunction, [fl.ap])])
+);
+
+
+const ap = curryN(2, (applyF, applyX) => {
+  // return original ramda `ap` if not Apply spec
+  if (!isApply(applyF) || !isApply(applyX)) { return apR(applyF, applyX) }
+
+  try {
+    // new version of `ap` starting from ramda version > 0.23.0
+    return applyF.ap(applyX);
+  } catch (e) {
+    // old version of `ap` till ramda version <= 0.23.0
+    return applyX.ap(applyF);
+  }
+});
+
+
+export default ap;

src/liftFN.js

@@ -1,22 +1,6 @@
-import { curry, head, slice, reduce, ap as apR, curryN, map, add, flip } from 'ramda';
+import { curry, head, slice, reduce, curryN, map } from 'ramda';
 
-import Identity from './internal/fantasy-land/Identity';
-
-const m1 = Identity.of(1);
-const m2 = Identity.of(2).map(add);
-
-
-export const createAp = (ap1, ap2) => {
-  try {
-    // new version of `ap` starting from ramda version > 0.23.0
-    return ap1.ap(ap2) && apR;
-  } catch (e) {
-    // old version of `ap` till ramda version <= 0.23.0
-    return curryN(2, flip(apR));
-  }
-};
-
-const ap = createAp(m2, m1);
+import ap from './internal/ap';
 
 /**
  * "lifts" a function to be the specified arity, so that it may "map over" objects that satisfy

test/internal/ap.js

@@ -0,0 +1,23 @@
+import { add, multiply } from 'ramda';
+
+import eq from '../shared/eq';
+import _ap from '../../src/internal/ap';
+import Identity from '../../src/internal/fantasy-land/Identity';
+
+
+describe('ap', function() {
+  const m1 = Identity.of(1);
+  const m2 = Identity.of(2).map(add);
+
+  it('tests new fantasyland spec compatibility', function() {
+    eq(_ap(m1, m2), Identity.of(3));
+  });
+
+  it('tests old fantasyland spec compatibility', function() {
+    eq(_ap(m2, m1), Identity.of(3));
+  });
+
+  it('tests for non Apply spec', function() {
+    eq(_ap([multiply(2), add(3)], [1, 2, 3]), [2, 4, 6, 4, 5, 6]);
+  });
+});

test/liftFN.js

@@ -4,7 +4,6 @@ import { add, reduce } from 'ramda';
 
 import RA from '../src/index';
 import eq from './shared/eq';
-import { createAp } from '../src/liftFN';
 import Identity from '../src/internal/fantasy-land/Identity';
 
 
@@ -50,27 +49,4 @@ describe('liftFN', function() {
     eq(typeof f4, 'function');
     eq(f4(addN)(Maybe.Some(1), Maybe.Some(1), Maybe.Some(1), Maybe.Some(1)), Maybe.Some(4));
   });
-
-  it('test old fantasyland spec compatibility', function() {
-    const m1 = Identity.of(1);
-    const m2 = Identity.of(2).map(add);
-
-    eq(createAp(m1, m2)(m1, m2), Identity.of(3));
-  });
-
-  it('test new fantasyland spec compatibility', function() {
-    const m1 = Identity.of(1);
-    const m2 = Identity.of(2).map(add);
-    const ap = createAp(m1, m2);
-
-    eq(ap(m1, m2), Identity.of(3));
-  });
-
-  it('test old fantasyland spec compatibility', function() {
-    const m1 = Maybe.Some(1);
-    const m2 = Maybe.Some(2).map(add);
-    const ap = createAp(m1, m2);
-
-    eq(ap(m1, m2), Maybe.Some(3));
-  });
 });

test/mocha.opts

@@ -1,4 +1,4 @@
 --reporter mocha-multi-reporters
 --reporter-options configFile=test/mocha-multi.json
 --compilers babel-register
-test/*.js
+test/**/*.js