Switch Branch + Block Scope : ECMAScript

explanation.md

Block scope can be used in switch statements. It's sort of a nice syntax that allows you to defined same-named variables without getting 'already defined' errors.

The example is not so great because data could be rewritten to be let data; at the top of the function, rather than in each case block.

Blocking scoping is pretty useful.

switch_blocks.js

async function branchOnAction( event ) {
  let response;
  switch( event.action ) {
    case 'create': {
      const data = Object.assign( {method:'POST'}, event.data );
      response = await req(data);
      break;
    } case 'read': {
      const data = Object.assign( {method:'GET'}, event.data );
      response = await req(data);
      break;
    } case 'update': {
      const data = Object.assign( {method:'PATCH'}, event.data );
      response = await req(data);
      break;
    } case 'delete': {
      const data = Object.assign( {method:'DELETE'}, event.data );
      response = await req(data);
      break;
    }
  }
  return response; 
}