node.js - Simple flow control in NodeJs -

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i've read through number of examples , tutorials , although know solution simple can't brain wrapped around it. here appreciated.

i have 2 functions in node. functiona() takes no arguments , returns string in english. second, functionb(english) takes english string returned funcitona() , translates language.

i believe callback best solution here life of me can't figure out best structure be.

thanks in advance.

i'm little unclear you're looking (you might overthinking things) consider following illustrates 4 ways of these functions being called , calling amongst themselves. clarification, should note not writing node-style callbacks, take form callback(err,result) in err evaluates false if there no error. don't have write own callbacks way, although tend myself.

// 'functiona' function getmessage(){     return 'hello'; };  // 'functionb' function francofy(str) {     var result;     switch(str){         case 'hello':             result = 'bon jour'; // 'allo' might better choice, let's stick node             break;         default:             throw new error('my vocabulary limited');     }     return result; };  // straightforward use of these functions  console.log('synch message, synch translate', francofy(getmessage()));  // if translation asynch - example, you're calling off api  // let's simulate api delay settimeout function contemplatetranslation(str,cb) {     settimeout(function(){         var result = francofy(str);         cb(result);     },1000); };  contemplatetranslation(getmessage(), function(translated){     console.log('synch message, asynch translate: ' + translated); });  // if message async? function getdelayedmessage(cb) {     settimeout(function(){         cb('hello');     },1000); };  getdelayedmessage(function(msg){    console.log('asynch message, synch translate', francofy(msg)); });  // if need call asynchronous api message , // call asynchronous api translate it?  getdelayedmessage(function(msg){     contemplatetranslation(msg, function(translated){         console.log("my god, it's full of callbacks", translated);     }); });

note there other ways deal asynchronous operations, such promises (i prefer q promise library myself, there other options). however, worth understanding core behavior before overlay abstractions on it.


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