Stop using Foo Bar!

rubyonrails-talk
1

Hi there,

I'm teaching myself RoR, and I've found myself on this forum a fair few times when looking for solutions to problems.

I've also found many other sites with help forums and tutorials as well.

This may seem like a petulant request, but please for the love of all things holy, can people stop using foo and bar in code demos and tutorials please?

It may be because I'm very new to this and I have to work through every step one by one, but I can't help being reminded of those IQ test questions e.g:

"All Blobs are Zweezils, and some Zweezils are BoingBoings, does this mean all Blobs are BoingsBoings?"

I'm guessing the nerdier among you felt the need to figure that one out. But if I'd written:

"All RoR developers are nerds; some nerds are uncomfortable in social situations. Does this mean all RoR developers are uncomfortable in social situations?

I assume most of you made sense of that immediately and came up with the answer 'no'.

Using Foo and Bar, just seems to add another level of mental processing to go through before you can start grasping the concepts of what's being explained.

I appreciate that sometimes, real world examples might make it more complicated if the words/variable names being used seem to overlap with what might be Ruby code (to a newbie at least).

Can I just ask for a little bit of imagination when giving examples please?

(Sorry to come on here and rant in my first ever post, I just figured this would be a good place to get it seen - I hope I'm not alone in my frustration).

Cheers,

Jules.

2

Can I just ask for a little bit of imagination when giving examples please?

No.

Longer version: programming is dealing with abstractions. If one want to learn programming then it is unavoidable. Or maybe I am just spoiled by those math teachers who used a and b, x, y and z instead of trying to come up with something more imaginative.

Regards, Rimantas

3

You can always use Voo, Doo, and Vlad. Metasyntactic variables are not meant to be creative or original though. They are simply meant to represent unknown variables. The common ones are Foo, Bar, and Baz.

4

Jules Copeland wrote:

Using Foo and Bar, just seems to add another level of mental processing to go through before you can start grasping the concepts of what's being explained.

I'm sure this is not the answer you're looking for, but I'm afraid you're going to have to learn to live with foo, bar, baz and foobar. These reference placeholders have been in use as long as I've been programming computers. It's such an ingrained part of the programmer's culture it will likely never disappear.

That being said. These placeholders are very often misused.

"They are commonly used to represent unknown values, typically when describing a scenario where the purpose of the unknown values is understood, but their precise values are arbitrary and unimportant." -- Ref: Foobar - Wikipedia

What you are describing is a scenario where the unknown values may not be understood, and their values are rational and important. In these scenarios good tutorials should avoid arbitrary references placeholders and use more descriptive examples.

Example:

def foo   bar = 10   baz = 5   foobar = bar + baz end

In such an example the meaning should be clear because the placeholders are truly arbitrary and unimportant. Any attempt to assign meaning to the variable severs no apparent purpose.

5

I just don't see the point in adding an extra layer of abstraction where there doesn't need to be one...

Most RoR evangelists go on about the readability of the code, so why spoil it by putting gibberish in?

If you're going to the effort of trying to explain something to someone, why not make the explanation as clear as possible?

6

c.f. <http://tools.ietf.org/html/rfc3092&gt;

7

What you are describing is a scenario where the unknown values may not be understood, and their values are rational and important. In these scenarios good tutorials should avoid arbitrary references placeholders and use more descriptive examples.

Example:

def foo   bar = 10   baz = 5   foobar = bar + baz end

In such an example the meaning should be clear because the placeholders are truly arbitrary and unimportant. Any attempt to assign meaning to the variable severs no apparent purpose.

Very good point. I don't have a problem with them in those kind of very trivial examples, but once things start getting more complex, the use of foobar just makes it harder to understand.

8

I'm teaching myself RoR, and I've found myself on this forum a fair few times when looking for solutions to problems.

I've also found many other sites with help forums and tutorials as well.

This may seem like a petulant request, but please for the love of all things holy, can people stop using foo and bar in code demos and tutorials please?

Yes, it's a petulant request. Welcome to programming. There's a culture and a tradition here. You aren't going to change it. Foo and bar (and baz, and quux -- see metasyntactic variable for more) are part of that culture tradition.

It may be because I'm very new to this and I have to work through every step one by one

[...]

Yes, you're very new. When entering a new culture, try not to play the "ugly American" and expect the culture to change and suit you. (Disclosure: I am a US citizen and as liable to be labeled an "ugly American" as anyone else.)

Using Foo and Bar, just seems to add another level of mental processing to go through before you can start grasping the concepts of what's being explained.

You need to learn the jargon when entering any field. When it comes to programming, you need to understand bits, bytes, floating point number, a million other things and, yes, foo and bar and friends.

I appreciate that sometimes, real world examples might make it more complicated if the words/variable names being used seem to overlap with what might be Ruby code (to a newbie at least).

Can I just ask for a little bit of imagination when giving examples please?

No. The point of foo and bar, which you have so blithely missed, is to avoid details that would distract from the meat of what is being discussed. When you see something like:

module Foo   def do_foo     puts "Foo!"   end end

class Bar   include Foo   def do_foo     puts "Bar!"   end end

...you can immediately tell that we're looking at an example of whether a method in an included module is overridden by a method in the including class or not (hint: it is). Those placeholders could be absolutely anything, but using foo and bar make it clear that the names should not be the focus of your attention.

(Sorry to come on here and rant in my first ever post, I just figured this would be a good place to get it seen - I hope I'm not alone in my frustration).

You may not be alone in your frustration, but you need to get over it. Why do algebra examples typically use x, y, and z as variables? Culture and tradition. I wouldn't expect that to change, ever, and you shouldn't expect foo, bar, baz, etc. to change, either.

Cheers, Jules.

--Greg P.S. Sorry to be grumpy, but I now understand how many Parisians feel about      most American tourists.

9

Jules Copeland wrote:

I just don't see the point in adding an extra layer of abstraction where there doesn't need to be one...

I'd suggest picking another battle to fight. This one is arbitrary and unimportant. It's not a battle you can win. You're focusing the blame for bad tutorial examples in the wrong place anyway.

The use of foo as a variable placeholder is no difference than using x in mathematics to represent a reference to an arbitrary value. There are a lot of people that also have trouble with this abstraction and find algebra difficult to grasp. That does not mean that math instructors should stop using x, y and z as abstract placeholders to unknown values in a equation.

10

Part of the problem with more ‘realistic’ variable names is that some people will fixate on the names and fail to notice the general principal. For example

def has_min_elements?(foo, bar)

foo.size >= bar

end

might be harder to read for someone new but

def bookshelf_has_at_least(bookshelf, number_of_books)

bookshelf.size > number_of_books

end

will have some people thinking about bookshelves and completely missing the fact that ‘bookshelf’ is an arbitrary name for an instance of an Array or Hash (possibly a String even).

I used to teach Prolog and the unlearning that had to take place after they wrote their first family tree program because the predicates had names like isa, parent and grandparent was a constant impediment. They understood the program very quickly but completely failed to understand Prolog. I ended up having to do search and replace on predicate and variable names to turn them into gibberish just to show them that the predicate and variable names had nothing to do with the how the program worked.

Learning means getting out of your comfort zone.

Besides Foo, Bar and Baz (along with xyzzy and plover) have a long and distinguished history.

11

Foo and Bar are the conceptual equivalent of using lorem ipsum when designing web pages. They're obviously not real things and so don't distract the user's attention away from the bigger picture.

I do agree with some people here who've pointed out that as soon as variables hold something meaningful (eg inside a method) then you should give them neaningful names, but that's not quite the same thing.

What i did find a little confusing with learning rails was the canonical example of a blog that has_many posts, that has_many comments. Once rest came along, i was learning that as well as ajax, i really wished one of the example models wasn't called 'post'. I was seeing stuff like

link_to "Post", post_path(post), :method => :post

which is a bit confusing.

(this precise example may not make sense but you get the general idea)

12

Wow - I didn't realise this would be such an emotive topic!

Thanks for all your replies.

You all make good points. I didn't mean to come across as aggressive, so apologies to all those who have come to the defence of your beloved metasyntactic variables! (Thanks for teaching me a new piece of jargon btw).

(On a related point - my friend just pointed me towards Why's Poignant Guide to Ruby - just had a quick scan through... the examples in there are awesome).

13

Jules Copeland wrote:

Hi there,

I'm teaching myself RoR, and I've found myself on this forum a fair few times when looking for solutions to problems.

Hello, friend. Stay a while, and listen. (Diablo I)

I've also found many other sites with help forums and tutorials as well.

This may seem like a petulant request, but please for the love of all things holy, can people stop using foo and bar in code demos and tutorials please?

I sense a soul in search of answers. (Diablo I)

It may be because I'm very new to this and I have to work through every step one by one, but I can't help being reminded of those IQ test questions e.g:

"All Blobs are Zweezils, and some Zweezils are BoingBoings, does this mean all Blobs are BoingsBoings?"

I'm guessing the nerdier among you felt the need to figure that one out.

Wrong - everybody figured that one out as soon as they read it. (Me)

Using Foo and Bar, just seems to add another level of mental processing to go through before you can start grasping the concepts of what's being explained.

That's interesting; I just tweeted a link to a really, really interesting article about programming and thinking:

Do read it all. I hope you find it enlightening. Consider "Foo" and "Bar" to be like scrubbing the floor and painting the fence in the movie "The Karate Kid". Reading them is tricky at first, but when you get used to them, you have learned a skill, whether you realize it or not.

14

Jules Copeland wrote:

Wow - I didn't realise this would be such an emotive topic!

Think of it this way, you've stepped into the middle of a new culture with a strong tradition and history. There are unwritten and abstract rules unknown to you.

It may seem perfectly reasonable to, for example, extend your left hand to someone in greeting. This may, in certain cultures, invoke a very different response than you might expect. Chance are, you'll be forgiven the gesture being of foreign origin, but that does not change the culture, nor the emotions behind the implied meaning of the gesture.

(On a related point - my friend just pointed me towards Why's Poignant Guide to Ruby - just had a quick scan through... the examples in there are awesome).

For a little more meat on this subject, and also server to illustrate some of my earlier points about the common misuse of foo (and family) see:

15

Jules Copeland wrote:

Hi there,

I'm teaching myself RoR, and I've found myself on this forum a fair few times when looking for solutions to problems.

I've also found many other sites with help forums and tutorials as well.

This may seem like a petulant request, but please for the love of all things holy, can people stop using foo and bar in code demos and tutorials please?

It may be because I'm very new to this and I have to work through every step one by one, but I can't help being reminded of those IQ test questions e.g:

"All Blobs are Zweezils, and some Zweezils are BoingBoings, does this mean all Blobs are BoingsBoings?"

I'm guessing the nerdier among you felt the need to figure that one out. But if I'd written:

"All RoR developers are nerds; some nerds are uncomfortable in social situations. Does this mean all RoR developers are uncomfortable in social situations?

I assume most of you made sense of that immediately and came up with the answer 'no'.

Using Foo and Bar, just seems to add another level of mental processing to go through before you can start grasping the concepts of what's being explained.

I appreciate that sometimes, real world examples might make it more complicated if the words/variable names being used seem to overlap with what might be Ruby code (to a newbie at least).

Can I just ask for a little bit of imagination when giving examples please?

(Sorry to come on here and rant in my first ever post, I just figured this would be a good place to get it seen - I hope I'm not alone in my frustration).

Cheers,

Jules.

I actually agree with you, but I still like using it because Foobar is an old Military term from Fubar which I used to use all the time. Anyone wanna take a stab at what "Fubar" means? :wink:

I'll give you a hint.

____ Up Beyond All Recognition

Try having that one stuck in your head everytime you see an example.

~Jeremy

16

Not to mention popular spinoffs like FooCamp and BarCamp.

17

I think there is a difference between the case when the two variables are genuinely independant as opposed to one where there is some relationship between the two *and* that relationship is an inherent part of the example being discussed (and where I doing maths I would convey that by using x_a and x_b or x and x' or something like that). I also wouldn't try and be needlessly obtuse ie

foos = Foo.all bars = Bar.find ...

rather than

bar = Foo.all baz = Bar.find ...

Fred

18

Frederick Cheung wrote:

I also wouldn't try and be needlessly obtuse ie

foos = Foo.all bars = Bar.find ...

rather than

bar = Foo.all baz = Bar.find ...

You're right. Read the article I linked to. It talks about consistency. :wink:

19

Frederick Cheung wrote:

a lot of people that also have trouble with this abstraction and find algebra difficult to grasp. That does not mean that math instructors should stop using x, y and z as abstract placeholders to unknown values in a equation.

I think there is a difference between the case when the two variables are genuinely independant as opposed to one where there is some relationship between the two *and* that relationship is an inherent part of the example being discussed (and where I doing maths I would convey that by using x_a and x_b or x and x' or something like that).

This is what I've been trying to say - thank you for putting it more succinctly.

When the variables have some kind of relationship to each other, using utterly arbitrary words really does detract from the example.

Seeing as a lot of RoR deals with data from a relational database, using foo bar makes it much harder to understand - especially in the case of a code snippet where you can't see the class declarations and relevant relationships.

20

It's not April 1st yet, fix your clock.

-Kyle