ng g input.mergeMap is not a function

ng g app-shell works on a fresh app but on my project I get the following error but no idea what it means

TypeError: input.mergeMap is not a function
    at Object.callRule (/node_modules/@angular-devkit/schematics/src/rules/call.js:70:18)
    at SchematicImpl.call (/node_modules/@angular-devkit/schematics/src/engine/schematic.js:35:23)
    at Promise (/node_modules/@angular/cli/tasks/schematic-run.js:73:23)
    at new Promise (<anonymous>)
    at Class.run (/node_modules/@angular/cli/tasks/schematic-run.js:72:16)
    at Class.run (/node_modules/@angular/cli/commands/generate.js:152:33)
    at resolve (/node_modules/@angular/cli/ember-cli/lib/models/command.js:261:20)
    at new Promise (<anonymous>)
    at Class.validateAndRun (/node_modules/@angular/cli/ember-cli/lib/models/command.js:240:12)
    at Promise.resolve.then.then (/node_modules/@angular/cli/ember-cli/lib/cli/cli.js:140:24)

The only thing I can think of is it’s a multi app setup structured like

src
  -- client
      -- app
  -- admin
      -- app
  -- environments

but I’ve tried setting the root and get the same result

ng generate app-shell [ --universal-app universal --root src/client ]

[BenevidesLecontes]

I was able to fix installing this locally @angular-devkit/schematics@0.0.40

[joseques]

It seems that if you have @angular/cli installed globally and a different version installed locally it gets broken. I solved the same error removing the cli package that was installed locally with npm remove @angular/cli --save in my project folder.