5 ms·

`Bind` with named methods goes a long way to cleaning up nested callbacks. Here's a (quick+dirty; I know I'm missing some `do`'s in there) version of the same c

`Bind` with named methods goes a long way to cleaning up nested callbacks. Here's a (quick+dirty; I know I'm missing some `do`'s in there) version of the same code in CoffeeScript: _ = fileMenu: -> mainWindow.menu "File", (e,f) => this.onFile(e,f) onFile: (err,file) -> if err then throw err file.openMenu (e,m) => this.onOpenMenu(e,m) onOpenMenu: (err,menu) -> if err then throw err menu.item "Open", (e,i) => this.onOpen(e,i) onOpen: (err,item) -> if err then throw err mainWindow.getChild type('Window'), (e,d) => this.onDialog(e,d) onDialog: (err,dialog) -> if err then throw err #... _.fileMenu() ( `=>` is CoffeeScript for a function bound to the current scope )

flashingpumpkin 16y ago
We've adopted a way that allows us to do basically this: mainWindow.menu "File", (err, file)-> openMenu err, (err, menu)-> getItem err, "Open", (err, item)-> click err, item, (err)-> getChild err, getChildType("Window"), (err, dialog)-> if err? and err instanceof NoFileError # do stuff if err? and err instanceof InvalidClickError # do other stuff if err? throw err # do stuff with dialog if no err Each function takes as first argument an error and as last a callback. If there's an error, the function just passes the error up the callback stack until it gets dealed with. fun = (err, args..., callback) You can't pull that off if your code is heavily object oriented though: mainWindow.menu "File", (err, file)-> # If mainWindow.menu errors, file is undefined # and the call to openMenu throws an error file.openMenu err, (err, menu)-> # ... Breaking your code/api up with modules instead into classes fixes that.

flashingpumpkin 16y ago

We've adopted a way that allows us to do basically this: mainWindow.menu "File", (err, file)-> openMenu err, (err, menu)-> getItem err, "Open", (err, item)-> click err, item, (err)-> getChild err, getChildType("Window"), (err, dialog)-> if err? and err instanceof NoFileError # do stuff if err? and err instanceof InvalidClickError # do other stuff if err? throw err # do stuff with dialog if no err Each function takes as first argument an error and as last a callback. If there's an error, the function just passes the error up the callback stack until it gets dealed with. fun = (err, args..., callback) You can't pull that off if your code is heavily object oriented though: mainWindow.menu "File", (err, file)-> # If mainWindow.menu errors, file is undefined # and the call to openMenu throws an error file.openMenu err, (err, menu)-> # ... Breaking your code/api up with modules instead into classes fixes that.