6 ms·

Many interviewees, when presented with `say("hello")("world")`, understood that `say` was a function that returned a function, but few were able to actually imp

by Xavi 16y ago

Many interviewees, when presented with `say("hello")("world")`, understood that `say` was a function that returned a function, but few were able to actually implement `say`.

erikwiffin 16y ago
I like this question, and I've got something that works, but I'm not sure it's the prefered solution. function say(arg) { return function(word) { alert(arg + " " + word); }; } It solves "hello world", but wouldn't work for something like say("dogs")("and")("cats"). Are you expecting an arbitrary number of function returns?
- noblethrasher 16y ago
  According to the expected output, you'd need something like: function say(x) { return function (y) { alert( capitalize(x) + " " + capitalize(y)); } } Where capitalize makes the first character uppercase.
  - Xavi 16y ago
    Oops, that's a type-o. The capitalize doesn't need to change. Thanks for the heads up.
- Xavi 16y ago
  Yep, that is exactly the solution I would be looking for. I would be blown a way if someone came up with solution that could handle arbitrary function returns. My friend actually wrote an interesting article on the subject. Here's the link if you're interested: http://msdn.microsoft.com/en-US/scriptjunkie/gg575560.aspx http://msdn.microsoft.com/en-US/scriptjunkie/gg575560.aspx
  - jaysoo 16y ago
    Not exactly the same signature, but can handle arbitrary number of calls. var say = (function() { var savedArgs = []; return (function recurse () { if (arguments.length) { for (var i=0, arg; arg=arguments[i]; i++) { savedArgs.push(arg); } return recurse; } else { alert(savedArgs.join(' ')); savedArgs = []; } }); })(); // e.g. say('Hello')('World')('!!')(); // --> alerts "Hello World !!"
  - sibsibsib 16y ago
    here's the version I came up with, based on one I did in python. It's very similar to jaysoo's - needs a call with no args to terminate the list. I'm curious if there's a way to do this somehow without the terminator. I'm not a JS expert by any means, so if I'm doing something stupid in this code, I'd love to know. var say = function(word) { words = [word]; func = function(word2) { if (word2) { words.push(word2); return func; } else { print(words.join(' ')); } } return func; }; say('hello')('bob')('how you doing?')(); *note I have the function 'print' aliased to console.log for convenience.

by Xavi 16y ago

Many interviewees, when presented with `say("hello")("world")`, understood that `say` was a function that returned a function, but few were able to actually implement `say`.

erikwiffin 16y ago

I like this question, and I've got something that works, but I'm not sure it's the prefered solution. function say(arg) { return function(word) { alert(arg + " " + word); }; } It solves "hello world", but wouldn't work for something like say("dogs")("and")("cats"). Are you expecting an arbitrary number of function returns?

noblethrasher 16y ago
According to the expected output, you'd need something like: function say(x) { return function (y) { alert( capitalize(x) + " " + capitalize(y)); } } Where capitalize makes the first character uppercase.
- Xavi 16y ago
  Oops, that's a type-o. The capitalize doesn't need to change. Thanks for the heads up.
Xavi 16y ago
Yep, that is exactly the solution I would be looking for. I would be blown a way if someone came up with solution that could handle arbitrary function returns. My friend actually wrote an interesting article on the subject. Here's the link if you're interested: http://msdn.microsoft.com/en-US/scriptjunkie/gg575560.aspx http://msdn.microsoft.com/en-US/scriptjunkie/gg575560.aspx
- jaysoo 16y ago
  Not exactly the same signature, but can handle arbitrary number of calls. var say = (function() { var savedArgs = []; return (function recurse () { if (arguments.length) { for (var i=0, arg; arg=arguments[i]; i++) { savedArgs.push(arg); } return recurse; } else { alert(savedArgs.join(' ')); savedArgs = []; } }); })(); // e.g. say('Hello')('World')('!!')(); // --> alerts "Hello World !!"
- sibsibsib 16y ago
  here's the version I came up with, based on one I did in python. It's very similar to jaysoo's - needs a call with no args to terminate the list. I'm curious if there's a way to do this somehow without the terminator. I'm not a JS expert by any means, so if I'm doing something stupid in this code, I'd love to know. var say = function(word) { words = [word]; func = function(word2) { if (word2) { words.push(word2); return func; } else { print(words.join(' ')); } } return func; }; say('hello')('bob')('how you doing?')(); *note I have the function 'print' aliased to console.log for convenience.