v1.5.1: don't cause ursa-optional to install due to error messages

README.md

@@ -23,6 +23,13 @@ node.js
 npm install --save rsa-compat
 ```
 
+For **more efficient** RSA key generation:
+<small>(I dropped `ursa` as an "optional dependency" because the non-fatal error messages on unsupported platforms and node versions were confusing people, but I still recommend installing it)</small>
+
+```bash
+npm install --save ursa
+```
+
 **Node &lt; v6** support:
 
 ```bash

lib/rsa-ursa.js

@@ -1,6 +1,16 @@
 'use strict';
 
-var ursa = require('ursa-optional');
+var ursa;
+try {
+  ursa = require('ursa');
+} catch(e) {
+  try {
+    ursa = require('ursa-optional');
+  } catch(e2) {
+    throw e;
+  }
+}
+
 
 function notToJson() {
   return undefined;

node.js

@@ -23,11 +23,15 @@ function create(deps) {
   deps.NOBJ = {};
   deps.RSA = RSA;
 
+  try {
+    RSA._URSA = require('ursa');
+  } catch(e) {
     try {
       RSA._URSA = require('ursa-optional');
     } catch(e) {
       // ignore
     }
+  }
 
   RSA.utils = require('./lib/key-utils.js');
   RSA.utils.toWebsafeBase64 = function (b64) {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "rsa-compat",
-  "version": "1.5.0",
+  "version": "1.5.1",
   "description": "RSA utils that work on Windows, Mac, and Linux with or without C compiler",
   "main": "node.js",
   "bin": {
@@ -42,10 +42,10 @@
     "node-forge": "^0.6.41"
   },
   "optionalDependencies": {
-    "ursa-optional": "^0.9.4"
   },
   "trulyOptionalDependencies": {
     "buffer-v6-polyfill": "^1.0.3",
-    "ursa": "^0.9.4"
+    "ursa": "^0.9.4",
+    "ursa-optional": "^0.9.4"
   }
 }