function randomString(n,s){
	//
	// review..
	try{
		n = n || 16
		let b = new Uint8Array(n+1) // +1 for extra random value for initial start position
		crypto.getRandomValues(b)

		s = s || 'ABCDEFGHIJKLMNOPQRSTUWXYZabcdefghijklmnopqrstuvwxyz01234567890'  //-_'

		let aa = []
		let ii = 0
		let len = s.length
		// note: this might be biased? or might be bad to add seq random numbers? 
		for(let i = 0;i< b.length;i++){ // first value (index 0) to start in a random location.
			let v = b[i] 
			ii += v
			if(i > 0){ 
				let iii = ii%len
				let vv = s[iii]
				if(!vv)
					conole.log('out of range?',iii)
				aa.push(vv)
				}
			}//for
		
		let r = aa.join('')

		return r	
		}
	catch(e){
		//
		console.log('crypto not supported?')
		return Math.random().toString(36).substring(7) // till  crypto bug fix?
		}
	}

export default randomString