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Do you happen to have any example code? I've had some bad experiences with "callback hell," so it's interesting to see that there are ways to prevent it from b

• jowiar 12y ago
  For me, callback hell is a code smell - it means that I'm thinking imperatively and not, umm, eventedly. The general fix is to call something a component - give it a name and such, and have it fire some events that something else should listen to.
• untog 12y ago
  One of my favourite parts of Bluebird is the 'Promisify' function. It allows you to take existing Node modules and use them as promises. Here's an example of interating over an array of files, only writing ones that don't already exist: http://pastie.org/9559209 http://pastie.org/9559209 It's also one of the reasons that I've ended up liking CoffeeScript more - Promises have a lot of function() and return statements, CS makes that kind of code a lot cleaner. For instance, that JS could be this short in CS: Promise.filter files, (file) -> fs.existsAsync(file).then (doesExist) -> !doesExist .each (file) -> fs.writeFileAsync(file.filename,file.content) .then -> Promise.map files, (file) -> fs.readFileAsync(file,'UTF-8') .then (fileContents) -> console.log(fileContents); ### Will return: [ "File 1 Content", "File 4 Content", "File 3 Content" ] ### .catch (err) -> # This will catch any and all errors that happened above.