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composition

composition

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Compose generator and async/await middleware like koa. Allows to use both generator functions and async/await functions.

var compose = require('composition');
 
var stack = [];
 
// generator functions 
stack.push(function* (next) {
  yield next;
});
 
// regular functions that return anything 
// but they should be promises! 
stack.push(function (next) {
  return Promise.resolve(true);
});
 
// async/await functions 
stack.push(async function (next) {
  return await Promise.resolve(true);
});
 
// compose it into a function 
var fn = compose(stack);
 
// this function returns a promise 
fn.call(this).then(function (val) {
  console.log(val);
}).catch(function (err) {
  console.error(err.stack);
  process.exit(1);
})