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0 pointstdavis17y ago0 comments

Quoting an article on the topic:

Having ploughed through several tutorials, I did not find Ruby particularly "elegant", or its syntax particularly obvious. Much of it seemed ad hoc, thrown together, in particular when there were several different ways of doing something, and it seemed to be the philosophy of the language to provide all of them. I did not find its constructs as intuitive and natural as claimed, trying out simple coding examples proved as frustrating when things didn’t do what you’d suppose they’d do...

(http://www.bitwisemag.com/2/What-s-Wrong-With-Ruby)

I actually gave Ruby a shot, going through the interactive tutorial on http://tryruby.hobix.com. I couldn't do it very long, however, because it was completely ridiculous. In what world does it make sense for hash keys to double as string grep? For instance:

    my_string['foo'] = 'bar'

will replace the first instance of foo in my_string with bar?! WHY?! I can stick an exclamation point on the end of method calls... to signify mutation? WHY?! What twisted logic allows one to rationalize multiplying strings like:

    "5" * 2 == "55"

yet throw an exception for:

    2 * "5"

It makes absolutely no sense! And why would an integer have a method for converting itself to a string? Or an array? I found so many things in Ruby that made me think, "Okay, superficially that's really convenient and sorta cool... but it makes no sense and it is absolutely counter-intuitive. And I feel dirty using it, even if everybody is doing it." Some people, I assume, find Ruby to be "elegant" for the same reasons I find it to be "an abomination."

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11 comments · 5 top-level

demallien17y ago· 4 in thread

Well, I can answer at least a few of those 'WHY?!'s.

Firstly starting with my_string['foo'] = 'bar', this is a syntax that is used a lot in Ruby for anytime that you wish to recover a subset of a collection - you can use it with a Dir object for example to recover a subset of directories/files, or in the case of a hash, to recover the object stored at the key. The thing is that you need to think about it as being a subset operator, rather than an index operator.

The exclamation point at the end of a method name has no syntactic meaning - it is simply a naming convention used by the standard libraries to indicate when the method mutates the object or not. Same same for method names ending with a question mark, it's just a convention to indicate that the response will be a boolean.

As for the whole "5" * 2 vs. 2 * "5", I must admit to not understanding where you're coming from. I don't see how you could expect any other kind of behaviour from an object orientated language. Personally I don't like over-riding arithmetic operators for non-number types, for precisely this reason, but hey, some people like it, so why not?

Integers converting to strings? I think every language has that no? I mean there's always something like: sprintf(myStringPtr, "%d", myInteger); or cout << myInteger;

etc etc

By making this a standard method on all classes (to_s), Ruby makes it really easy to dump a class to a serial format, which is very useful for debugging, as an example.

I get the impression that you simply didn't spend enough time with Ruby to come to understand its idioms, in which case, you're not really in a position to effectively criticise the language...

tdavisOP17y ago

I suppose these just seem odd to me, which was my point. Not that I find something absolutely wrong about them, anymore than I can find something wrong about a language which doesn't have mutable variables or whatever the case may be.

A lot of Ruby's conventions simply scream "ambiguity" to me. A "subset of a collection" is extremely ambiguous; if there is more than 1 foo in my_string, does it always get the first? How do I get the rest? my_string['foo'][2] or something? I can't even intuitively make something up which makes sense to me. Perhaps there isn't a way to get the others, which I suppose would be in line with Python, which doesn't supply a string method to find all occurrences at once... but how do I offset it?

I can see where standardized methods like to_a can be more convenient, but they also open up the possibility for unlimited ambiguity. What does Foo.to_a do for your Foo class? It could do anything! There's no way I could rely on these methods to do something across the board unless I know your class conforms to some Interface (do Ruby folks use/have Interfaces?). In Python, if I do

  [foo]

Then foo is now a list. I always know what I'm getting. I always know what int() is going to attempt to do to an object, etc.

Freaky16y ago

Perhaps there isn't a way to get the others, which I suppose would be in line with Python, which doesn't supply a string method to find all occurrences at once... but how do I offset it?

Yes, there's no way to get the other matches using [] as far as I know, it's just a generalization of being able to pass various types to it; Fixnum, Range, Regexp.. I don't see the harm in doing something with String too. If you wanted to extract multiple items, you'd use something like String#scan, or if you wanted to do a global replace, String#gsub, which can also accept a code block to perform computed replacements.

I can see where standardized methods like to_a can be more convenient, but they also open up the possibility for unlimited ambiguity. What does Foo.to_a do for your Foo class?

As of 1.9, it does this:

    NoMethodError: undefined method `to_a' for Foo:Class

In 1.8 it issues "warning: default `to_a' will be obsolete".

In Python, if I do `[foo]` Then foo is now a list.

You do the exact same thing in Ruby, though if you're wanting to cast your argument like the old to_a did, you use Array(), which won't turn [] into [[]]. If you want a number, Integer() or Float() will raise an exception if they can't give you one.

earthboundkid16y ago

"As for the whole "5" * 2 vs. 2 * "5", I must admit to not understanding where you're coming from. I don't see how you could expect any other kind of behaviour from an object orientated language."

Python has a __rmult__ method. If you do A * B, first it internally calls A.__mult__(B) then if that raises TypeError, it tries B.__rmult__(A). It's pretty elegant, I think. For Ruby, it wouldn't look as nice to do A.r* though, I guess, but it would be a nice bit of functionality.

Herring16y ago

>I get the impression that you simply didn't spend enough time with Ruby to come to understand its idioms, in which case, you're not really in a position to effectively criticise the language...

Well yeah like others have been saying, python is more attractive to new users is probably partly why it's more popular. You don't need to work as hard to understand its idioms, it's more readable by newbies (by anyone), etc.

wildjim17y ago· 1 in thread

Re: "5" 2 == "55" vs. 2 * "5" == Exception*

You need to remember that EVERYTHING is an object, there are no basic/literal types at all; in this case, "5" is really just syntactic sugar for creating a "5" String object, 2 is syntactic sugar for creating the "2" Integer (Number?) object, and the " * " operator is syntactic sugar for the " * " method of the "5" String object == ' "5".times(2) ' (which is similar to Perl's ' "5" x 2 ' construct).

The String class supports a " * " method which creates n copies of it's string value, and concat's them together into a new String object, but the Integer class does not.

Many "basic" objects have explicit conversion methods, but will also frequently support implicit conversion where it makes sense.

akho16y ago

Why does it overload "*" on the right, but not on the left side of the string? Python has __rmult__, and it works. Please do not try to make language warts look better by spilling a bucket of architectural-astronauty crap.

biaxident17y ago· 1 in thread

"5" * 2 == "55"

You're calling a method on a string, so you got the string doubled. Seems to make sense to me.

Obviously in this case the order of the arguments matter.

earthboundkid16y ago

"Obviously in this case the order of the arguments matter."

It's not obvious in terms of intuitiveness, no. Why not extend the Integer class to know to call mystring's * method when their order is reversed? That would be intuitive.

halostatue16y ago

Huntbach's article was pure nonsense when it was written[1], and it remains pure nonsense now.

[1] As I wrote two years ago: http://www.halostatue.ca/2007/03/17/whats-wrong-with-bitwise...

earthboundkid16y ago

"And why would an integer have a method for converting itself to a string? Or an array?"

You know that under the covers in Python str(1) works by calling (1).__str__(), right? That's why you can make str(my_custom_class) work.

j / k navigate · click thread line to collapse

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11 comments · 5 top-level

demallien17y ago· 4 in thread

Well, I can answer at least a few of those 'WHY?!'s.

Integers converting to strings? I think every language has that no? I mean there's always something like: sprintf(myStringPtr, "%d", myInteger); or cout << myInteger;

etc etc

By making this a standard method on all classes (to_s), Ruby makes it really easy to dump a class to a serial format, which is very useful for debugging, as an example.

I get the impression that you simply didn't spend enough time with Ruby to come to understand its idioms, in which case, you're not really in a position to effectively criticise the language...

tdavisOP17y ago

  [foo]

Then foo is now a list. I always know what I'm getting. I always know what int() is going to attempt to do to an object, etc.

Freaky16y ago

Perhaps there isn't a way to get the others, which I suppose would be in line with Python, which doesn't supply a string method to find all occurrences at once... but how do I offset it?

I can see where standardized methods like to_a can be more convenient, but they also open up the possibility for unlimited ambiguity. What does Foo.to_a do for your Foo class?

As of 1.9, it does this:

    NoMethodError: undefined method `to_a' for Foo:Class

In 1.8 it issues "warning: default `to_a' will be obsolete".

In Python, if I do `[foo]` Then foo is now a list.

earthboundkid16y ago

"As for the whole "5" * 2 vs. 2 * "5", I must admit to not understanding where you're coming from. I don't see how you could expect any other kind of behaviour from an object orientated language."

Herring16y ago

>I get the impression that you simply didn't spend enough time with Ruby to come to understand its idioms, in which case, you're not really in a position to effectively criticise the language...

wildjim17y ago· 1 in thread

Re: "5" 2 == "55" vs. 2 * "5" == Exception*

The String class supports a " * " method which creates n copies of it's string value, and concat's them together into a new String object, but the Integer class does not.

Many "basic" objects have explicit conversion methods, but will also frequently support implicit conversion where it makes sense.

akho16y ago

biaxident17y ago· 1 in thread

"5" * 2 == "55"

You're calling a method on a string, so you got the string doubled. Seems to make sense to me.

Obviously in this case the order of the arguments matter.

earthboundkid16y ago

"Obviously in this case the order of the arguments matter."

It's not obvious in terms of intuitiveness, no. Why not extend the Integer class to know to call mystring's * method when their order is reversed? That would be intuitive.

halostatue16y ago

Huntbach's article was pure nonsense when it was written[1], and it remains pure nonsense now.

[1] As I wrote two years ago: http://www.halostatue.ca/2007/03/17/whats-wrong-with-bitwise...

earthboundkid16y ago

"And why would an integer have a method for converting itself to a string? Or an array?"

You know that under the covers in Python str(1) works by calling (1).__str__(), right? That's why you can make str(my_custom_class) work.

j / k navigate · click thread line to collapse