output ES modules to better support tree-shaking, closes gcanti#326

.gitignore

@@ -1,6 +1,7 @@
 *.log
 node_modules
 lib
+es6
 dev
 coverage
 declaration/out/src

CHANGELOG.md

@@ -14,6 +14,10 @@
 **Note**: Gaps between patch versions are faulty/broken releases. **Note**: A feature tagged as Experimental is in a
 high state of flux, you're at risk of it changing without notice.
 
+# 1.8.6
+
+output ES modules to better support tree-shaking, closes #326 (@gcanti)
+
 # 1.8.5
 
 - **Bug Fix**

package.json

@@ -1,20 +1,23 @@
 {
   "name": "io-ts",
-  "version": "1.8.5",
+  "version": "1.8.6",
   "description": "TypeScript compatible runtime type system for IO validation",
   "files": [
-    "lib"
+    "lib",
+    "es6"
   ],
   "main": "lib/index.js",
+  "module": "es6/index.js",
   "typings": "lib/index.d.ts",
+  "sideEffects": false,
   "scripts": {
     "lint": "tslint -p tsconfig.json src/**/*.ts test/**/*.ts",
     "jest": "jest",
     "prettier": "prettier --no-semi --single-quote --print-width 120 --parser typescript --list-different \"{src,test}/**/*.ts\"",
     "fix-prettier": "prettier --no-semi --single-quote --print-width 120 --parser typescript --write \"{src,test,examples,exercises}/**/*.ts\"",
     "test": "npm run prettier && npm run lint && npm run dtslint && npm run declaration && npm run jest",
-    "clean": "rimraf lib/*",
-    "build": "npm run clean && tsc",
+    "clean": "rimraf lib/* es6/*",
+    "build": "npm run clean && tsc && tsc -p tsconfig.es6.json",
     "prepublish": "npm run build",
     "perf": "node perf/index",
     "dtslint": "dtslint dtslint",

tsconfig.es6.json

@@ -0,0 +1,7 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "outDir": "./es6",
+    "module": "es6"
+  }
+}