initLernaDemo

lerna init
$lernajson = Get-Content lerna.json -Raw | ConvertFrom-Json
Add-Member -InputObject $lernajson -Name "npmClient" -Value "yarn" -MemberType NoteProperty;
$lernajson | ConvertTo-Json | Set-Content ".\lerna.json";
mkdir packages
cd .\packages
mkdir app
cd app
yarn init -y
@"
var alpha = require('alpha');
var beta = require('beta');
console.log(alpha + " " + beta);
"@ | Set-Content index.js
$packagejson = Get-Content package.json | ConvertFrom-Json;
$dependencies = @"
{
  "alpha": "1.0.0",
  "beta": "1.0.0"  
}
"@ | ConvertFrom-Json;
Add-Member -InputObject $packagejson -Name "dependencies" -Value $dependencies -MemberType NoteProperty;
$packagejson | ConvertTo-Json | Set-Content ".\package.json";
cd ..
mkdir alpha
cd alpha
yarn init -y
@"
module.exports = 'alpha';
"@ | Set-Content index.js
cd ..
mkdir beta
cd beta
yarn init -y
@"
module.exports = 'beta';
"@ | Set-Content index.js
cd ..\..
lerna bootstrap --npm-client=yarn
ls | tree /f