update to use crypto when available

Author: Chris Cavalea

CHANGELOG.md

@@ -0,0 +1,5 @@
+## 1.0.1
+* updated default engine to use native Crypto, with Math.random as fallback.
+
+## 1.0.0
+Initial release.

README.md

@@ -36,7 +36,7 @@ import { bool, intRange } from 'aimless.js'
 
 ## Using Custom PRNG
 
-Aimless.js is compatible with any custom PRNG that returns a number between 0 and 1 inclusively.  Every function accepts an `engine` to be used.  Every function will default to using `Math.random` if no `engine` is provided.
+Aimless.js is compatible with any custom PRNG that returns a number `num >= 0` and `num < 1`.  Every function accepts an `engine` to be used.  Every function will default to using the provided `defaultEngine` if no `engine` is provided.  The `defaultEngine` uses `crypto.getrandomvalues` when available, with a fallback of `Math.random`.
 
 ```es6
 import { bool } from 'aimless.js'
@@ -200,7 +200,7 @@ Returns either `-1` or `1`.
 
 ### uniqFuncIntRange(min, max, engine)
 
-Returns a **unique** random number between `min` and `max`, using the provided `engine`.  If no `engine` is passed, `Math.random` will be used.  If there are no unique values left to return, `null` will be returned.
+Returns a **unique** random number between `min` and `max`, using the provided `engine`.  If no `engine` is passed, the defaultEngine will be used.  If there are no unique values left to return, `null` will be returned.
 
 ```es6
 const uniqueRNG = uniqFuncIntRange(1, 3)
@@ -212,7 +212,7 @@ uniqueRNG() // null
 
 ### uniqFuncSequence(array, engine)
 
-Returns a **unique** random number from the provided `array`, using the provided `engine`.  If no `engine` is passed, `Math.random` will be used.  If there are no unique values left to return, `null` will be returned.
+Returns a **unique** random number from the provided `array`, using the provided `engine`.  If no `engine` is passed, the defaultEngine will be used.  If there are no unique values left to return, `null` will be returned.
 
 ```es6
 const uniqueRNG = uniqFuncSequence([10, 20, 30])
@@ -249,4 +249,4 @@ Aimless relies on ES5 array methods, and is supported in all modern browsers.  S
 
 ## License
 
-[MIT](https://opensource.org/licenses/MIT). © 2023 Christopher Cavalea
+[MIT](https://opensource.org/licenses/MIT). © 2023 Christopher Cavalea

package-lock.json

@@ -4,7 +4,7 @@
   "main": "dist/aimless.js",
   "module": "dist/aimless.module.js",
   "jsnext:main": "dist/aimless.module.js",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "license": "MIT",
   "repository": "ChrisCavs/aimless.js",
   "author": {

package.json

@@ -1,11 +1,11 @@
 import { intRange } from './int-range'
-import { generateCurry } from './utils'
+import { defaultEngine, generateCurry } from './utils'
 
 /**
  * Returns a random boolean (true or false)
  * @param engine PRNG of choice
  */
-const bool = (engine = Math.random) => {
+const bool = (engine = defaultEngine) => {
   return !!intRange(0, 1, engine)
 }
 

src/bool.js

@@ -1,12 +1,12 @@
 import { intRange } from './int-range'
-import { generateCurry } from './utils'
+import { defaultEngine, generateCurry } from './utils'
 
 /**
  * Returns a random character from the provided array
  * @param str String
  * @param engine PRNG of choice
  */
-const char = (str, engine = Math.random) => {
+const char = (str, engine = defaultEngine) => {
   return str[intRange(0, str.length - 1, engine)]
 }
 

src/char.js

@@ -1,11 +1,11 @@
-import { generateCurry } from "./utils"
+import { defaultEngine, generateCurry } from "./utils"
 
 /**
  * Returns a random value that follows a custom distribution
  * @param func Distribution function that accepts a random number between 0 and 1
  * @param engine PRNG of choice
  */
-const customDist = (func, engine = Math.random) => {
+const customDist = (func, engine = defaultEngine) => {
   return func(engine())
 }
 

src/custom-dist.js

@@ -1,11 +1,11 @@
-import { generateCurry } from "./utils"
+import { defaultEngine, generateCurry } from "./utils"
 
 /**
  * Returns a random value that follows an exponential distribution
  * @param lambda Lambda
  * @param engine PRNG of choice
  */
-const exponentialDist = (lambda, engine = Math.random) => {
+const exponentialDist = (lambda, engine = defaultEngine) => {
   return -Math.log(1 - engine()) / lambda
 }
 

src/exponential-dist.js

@@ -1,12 +1,12 @@
-import { generateCurry } from "./utils"
+import { defaultEngine, generateCurry } from "./utils"
 
 /**
  * Returns a random number within the float range
  * @param min Minimum value
  * @param max Maximum value
  * @param engine PRNG of choice
  */
-const floatRange = (min, max, engine = Math.random) => {
+const floatRange = (min, max, engine = defaultEngine) => {
   return engine() * (max - min) + min
 }
 

src/float-range.js

@@ -1,12 +1,12 @@
-import { generateCurry, randIntRange } from './utils'
+import { defaultEngine, generateCurry, randIntRange } from './utils'
 
 /**
  * Returns a random number within the integer range
  * @param min Minimum integer
  * @param max Maximum integer
  * @param engine PRNG of choice
  */
-const intRange = (min, max, engine = Math.random) => {
+const intRange = (min, max, engine = defaultEngine) => {
   return randIntRange(min, max, engine)
 }
 

src/int-range.js

@@ -1,4 +1,4 @@
-import { generateCurry, generateListFromRange } from './utils'
+import { defaultEngine, generateCurry, generateListFromRange } from './utils'
 import { sequence } from './sequence'
 
 /**
@@ -7,7 +7,7 @@ import { sequence } from './sequence'
  * @param max Maximum value
  * @param engine PRNG of choice
  */
-const intSequence = (min, max, engine = Math.random) => {
+const intSequence = (min, max, engine = defaultEngine) => {
   return sequence(
     generateListFromRange(min, max),
     engine

src/int-sequence.js

@@ -1,12 +1,12 @@
-import { generateCurry } from "./utils"
+import { defaultEngine, generateCurry } from "./utils"
 
 /**
  * Returns a random value that follows a normal distribution
  * @param mean Mean
  * @param stdDev Standard Deviation
  * @param engine PRNG of choice
  */
-const normalDist = (mean, stdDev, engine = Math.random) => {
+const normalDist = (mean, stdDev, engine = defaultEngine) => {
   // Box-Muller transform
   let u, v, s
 

src/normal-dist.js

@@ -1,11 +1,11 @@
 import { floatRange } from './float-range'
-import { generateCurry } from './utils'
+import { defaultEngine, generateCurry } from './utils'
 
 /**
  * Returns a random number between -1 and 1
  * @param engine PRNG of choice
  */
-const normalFloat = (engine = Math.random) => {
+const normalFloat = (engine = defaultEngine) => {
   return floatRange(-1, 1, engine)
 }
 

src/normal-float.js

@@ -1,12 +1,12 @@
 import { intRange } from './int-range'
-import { generateCurry } from './utils'
+import { defaultEngine, generateCurry } from './utils'
 
 /**
  * Returns a random value from the provided array
  * @param arr Array of values
  * @param engine PRNG of choice
  */
-const oneOf = (arr, engine = Math.random) => {
+const oneOf = (arr, engine = defaultEngine) => {
   return arr[intRange(0, arr.length - 1, engine)]
 }
 

src/one-of.js

@@ -1,12 +1,12 @@
 import { intRange } from './int-range'
-import { generateCurry, sliceOut } from './utils'
+import { defaultEngine, generateCurry, sliceOut } from './utils'
 
 /**
  * Returns a new array with randomized order
  * @param arr Array of values
  * @param engine PRNG of choice
  */
-const sequence = (arr, engine = Math.random) => {
+const sequence = (arr, engine = defaultEngine) => {
   const result = []
 
   let tempArr = arr

src/sequence.js

@@ -1,11 +1,11 @@
 import { bool } from './bool'
-import { generateCurry } from './utils'
+import { defaultEngine, generateCurry } from './utils'
 
 /**
  * Returns a random sign (-1 or 1)
  * @param engine PRNG of choice
  */
-const sign = (engine = Math.random) => {
+const sign = (engine = defaultEngine) => {
   return bool(engine) ? 1 : -1
 }
 

src/sign.js

@@ -1,4 +1,4 @@
-import { generateListFromRange } from './utils'
+import { defaultEngine, generateListFromRange } from './utils'
 import uniqFuncSequence from './uniq-func-sequence'
 
 /**
@@ -7,7 +7,7 @@ import uniqFuncSequence from './uniq-func-sequence'
  * @param max Maximum integer
  * @param engine Engine to be used as PRNG
  */
-const uniqFuncIntRange = (min, max, engine = Math.random) => {
+const uniqFuncIntRange = (min, max, engine = defaultEngine) => {
   return uniqFuncSequence(
     generateListFromRange(min, max),
     engine

src/uniq-func-int-range.js

@@ -1,11 +1,11 @@
-import { randIntRange, sliceOut } from './utils'
+import { defaultEngine, randIntRange, sliceOut } from './utils'
 
 /**
  * Returns a PRNG function that returns unique values from the provided array.
  * @param arr Array of values to pull from
  * @param engine Engine to be used as PRNG
  */
-const uniqFuncSequence = (arr, engine = Math.random) => {
+const uniqFuncSequence = (arr, engine = defaultEngine) => {
   let tempArr = arr
 
   return () => {

src/uniq-func-sequence.js

@@ -1,3 +1,20 @@
+const defaultEngine = () => {
+  try {
+    // Credit @ Tamás Sallai
+    const crypto = window.crypto || window.msCrypto
+    const buffer = new ArrayBuffer(8);
+    const ints = new Int8Array(buffer);
+    crypto.getRandomValues(ints);
+
+    ints[7] = 63;
+    ints[6] |= 0xf0;
+
+    return new DataView(buffer).getFloat64(0, true) - 1;
+  } catch (e) {
+    return Math.random()
+  }
+}
+
 const generateListFromRange = (min, max) => {
   const result = []
 
@@ -8,29 +25,29 @@ const generateListFromRange = (min, max) => {
   return result
 }
 
-export { generateListFromRange }
-
-const randIntRange = (i, j, engine = Math.random) => {
+const randIntRange = (i, j, engine = defaultEngine) => {
   const min = Math.ceil(i)
   const max = Math.floor(j)
 
   return Math.floor(engine() * (max - min + 1)) + min
 }
 
-export { randIntRange }
-
 const sliceOut = (arr, i) => {
   return arr.slice(0, i).concat(arr.slice(i + 1))
 }
 
-export { sliceOut }
-
 const generateCurry = (func) => {
-  return (engine = Math.random) => {
+  return (engine = defaultEngine) => {
     return (...args) => {
       return func(...args, engine)
     }
   }
 }
 
-export { generateCurry }
+export {
+  generateListFromRange,
+  randIntRange,
+  sliceOut,
+  generateCurry,
+  defaultEngine,
+}

src/utils.js

@@ -1,10 +1,10 @@
-import { generateCurry } from "./utils"
+import { defaultEngine, generateCurry } from "./utils"
 
 /**
  * Returns a valid RFC4122 version4 ID hex string, using the provided engine
  * @param engine PRNG of choice
  */
-const uuid = (engine = Math.random) => {
+const uuid = (engine = defaultEngine) => {
   // Credit @Alexey Silin from https://gist.github.com/1308368
   var a = ''
   var b = ''

src/uuid.js

@@ -1,12 +1,12 @@
-import { generateCurry } from "./utils"
+import { defaultEngine, generateCurry } from "./utils"
 
 /**
  * Returns a random value from the provided array, biased towards provided weights
  * @param nums Array of numbers (integer or float)
  * @param weights Array of weights (integer or float)
  * @param engine PRNG of choice
  */
-const weighted = (nums, weights, engine = Math.random) => {
+const weighted = (nums, weights, engine = defaultEngine) => {
   if (nums.length !== weights.length) {
     throw new Error('Every provided number must have a corresponding weight.')
   }