// By default Deno
use deno.land/x for packages registry.
deno add react react-dom // looking react and react-dom in deno.land/x and downloading if It's not appear in Deno local's library. but if it's already had package 'react' and 'react-dom' in local's it's will linked to downloaded package in local's deno developer machince.
deno update // update package that's shown in import_map.json or imports key in deno.json
deno remove react react-dom // remove package named 'react' and 'react-dom' in import_map.json or deno.json
deno delete react // to remove package named 'react' in import_map.json and also delete in Deno local's library.
// And user can also use other registry such as esm.sh, skypack, etc. by Using deno pkg <registry> to set registry source where developer would like to used. 
deno pkg esm // to use esm.sh as registry for deno add, update, remove commands.
deno pkg skypack // to use skypack as registry for deno add, update, remove commands.
deno pkg npm // to use npm as registry for deno add, update, remove commands.
deno pkg x // to use deno.land/x as registry for deno add, update, remove commands. (back to default registry)
deno pkg list // listing all package currently downloaded on developer's Deno local's library. show name, source(esm.sh, skypack, etc.) and version or more?
// By this way it's can extended developing experinces in Deno
to more widely. and improve productivity and take adventage of
millions of cdn library from many user's known registry can integrate with deno developer. made Deno
more easy and flexible to use.
// ref.
https://deno.land/x/esm@v134#using-cli-script