4 ms·

i know it's sort of side effect driven, but i like function hoisting. it's one of my main tools to fight the callback pyramid of doom. use named functions, pl

i know it's sort of side effect driven, but i like function hoisting. it's one of my main tools to fight the callback pyramid of doom. use named functions, place them below the code that uses them. all flat.

wakaflaka 12y ago
You are just asking for race condition issues with that type of "solution."
- andrey-p 12y ago
  You can still pass in callbacks to them. So if I got the parent's intent right, you've got: function bunchOfAsyncThings(callback) { var function1, function2; function1 = function (callback) { // do stuff here, then do callback function2(callback); }; function 2 = function (callback) { // done with everything callback(); }; function1(callback); } (Edit: formatting)
- Jare 12y ago
  Are you referring to a case like this? { f(); var a = 3; function f() { console.log(a); } } That will print "undefined" because the entire function f() is hoisted and callable in the first line, but the variable a has not yet been assigned the value. That's not a race condition (those are related to timing in concurrent systems) but is certainly the sort of counter-intuitive visibility that makes me prefer to use function expressions most of the time.
- pdpi 12y ago
  how, exactly, is that going to cause race conditions?
icebraining 12y ago
Why not do the reverse, and declare the inner functions before?
- AdrianRossouw 12y ago
  coffeescript forces you to do that, and I do use it that way sometimes in CS. I don't do it as much as i would with plain js, because the function definition feels less awkward, but I do still prefer named functions over anonymous ones. even if the name only exists in the local scope.
AdrianRossouw 12y ago
This is what I mean. The code that uses the callbacks go first, the callbacks themselves are all named and access to closures withstanding, not nested. // this is all the code that is used, var _changes = follow(couchOpts); _changes.on('change', onChange); _changes.on('error', onError); _changes.resume(); // from here is just named functions function onChange(data) { _changes.pause(); save(data.seqId, saveFn); } function saveFn(err, entity) { if (err) { return console.log(err); } _changes.resume(); } function onError(err) { console.log(err); }

wakaflaka 12y ago

You are just asking for race condition issues with that type of "solution."

andrey-p 12y ago
You can still pass in callbacks to them. So if I got the parent's intent right, you've got: function bunchOfAsyncThings(callback) { var function1, function2; function1 = function (callback) { // do stuff here, then do callback function2(callback); }; function 2 = function (callback) { // done with everything callback(); }; function1(callback); } (Edit: formatting)
Jare 12y ago
Are you referring to a case like this? { f(); var a = 3; function f() { console.log(a); } } That will print "undefined" because the entire function f() is hoisted and callable in the first line, but the variable a has not yet been assigned the value. That's not a race condition (those are related to timing in concurrent systems) but is certainly the sort of counter-intuitive visibility that makes me prefer to use function expressions most of the time.
pdpi 12y ago
how, exactly, is that going to cause race conditions?

icebraining 12y ago

Why not do the reverse, and declare the inner functions before?

AdrianRossouw 12y ago
coffeescript forces you to do that, and I do use it that way sometimes in CS. I don't do it as much as i would with plain js, because the function definition feels less awkward, but I do still prefer named functions over anonymous ones. even if the name only exists in the local scope.

AdrianRossouw 12y ago

This is what I mean. The code that uses the callbacks go first, the callbacks themselves are all named and access to closures withstanding, not nested. // this is all the code that is used, var _changes = follow(couchOpts); _changes.on('change', onChange); _changes.on('error', onError); _changes.resume(); // from here is just named functions function onChange(data) { _changes.pause(); save(data.seqId, saveFn); } function saveFn(err, entity) { if (err) { return console.log(err); } _changes.resume(); } function onError(err) { console.log(err); }