Why was my comment modded Troll? Some people totally lack a sense of humor! My comment was tongue-and-cheek, yet at the same time pointed to convey scientific fact. Geez, makes me wonder...
Mars!? You can't be serious! The sneaky devil might actually manage to survive...
Can you imagine what an upset it would be for the astronauts, when they arrive in 2030, only to find Darl suing the pants off the Martians? Just to be safe we had better send him off to Uranus!
If the United States institutes such a barbaric policy as a digital "lockdown", it would only have the effect of stifling technological innovation. This would be akin to committing economic suicide. A "zero-tolerance" policy for insecure software would sufficiently deter all but the wealthiest corporations from taking the risks associated with software development, but only in the US. The fear of accidentally introducing a defect, or vulnerability into a product would mean that the process of innovation itself becomes a liability. The lack of competitive pressure in the domestic market from smaller developers, would permit the larger software companies to slash research spending, in order to increase their profit margin; amid all of this they would become complacent. All of a sudden, software in the US would begin to look quite static when compared to the rest of the world (which by now is adopting Linux, and other OSS at an phenomenal rate). The gradual decrease in market share for US, in the software industry, becomes a flood. Pretty soon the US is behind the rest of the world in other sectors, as software in foreign countries becomes cheaper, faster, better and ironically, more secure.
If your definition of "whacko" includes someone with the training, discipline, fortitude, strength of mind and body, coupled with the shear will to survive the harsh conditions of Mars... Then I would place that kind of bet.
Given ten years to prepare, I would volunteer myself in an instant.
I'm not buying it either, and I agree with most of your assertions. In essence, the labels license music from an artist, and then sub-license it to consumers. The consumer can then make as many personal copies of the original as they like. The only stipulations relate to the distribution, broadcast, or public performance of the work in question. An artists royalties are proportional to the number of units sold (i.e. consumer licenses). Therefore, it would seem quite plausible that two copies of the same song could be construed as a single unit, provided they were sold to a one consumer as a single purchase item.
That's not Polymorphism, it's plain old static typing.
It is highly related to polymorphism. Was my original criticism entirely lost on you? I said dynamic typed languages do not support "true" polymorphism, because - as you mentioned - any class can be valid with any expression provided it contains the requisite method! For instance, classes "ShapeA" and "ShapeB" could both contain the method area(), allowing for the seemingly proper execution of code, while failing to extend the anticipated "BaseShape".
They don't complicate debugging at all - you see the traceback on exception, and notice what line of code calls a method that doesn't exist. Such errors are trivial to correct, and are not really all that common either (usually typos)
In most cases I would agree with you, but only if you assume the developer writing code using the function:
1. Has perfect documentation, and never forgets to implement a rarely used, but critical method; or
2. Has the source code so the he can see how the function works so that he can make sure he hasn't forgotten to implement a method that is only called in certain circumstances; or
3. Tests all possible input
That's because usually these checks are not made at all in dynamically typed languages. They are simply not needed.
Actually, in many cases these checks need to be made, especially within the scope of framework or toolkit development (of which I do a considerable amount).
It's a tradeoff, really. Dynamically typed languages lose some, and win a lot.
The gains decrease exponentially with the size, and complexity of the project.
Believe me, I used to think the way you do now before discovering Python.
Well I'll certainly give it a try. Please understand that I really have no prejudice when it comes to languages; they all have advantages, and disadvantages. What I'm attempting to do is make observations based around issues that dynamically typed languages have in common.
The most derived version of a method gets always called, unless you explicitly request less derived version. Just as in Java.
I don't think you understood my point... In Java the compiler would check the following definition to ensure that all objects passed to myFunction are of type MyClass or descended from it:
public void myFunction(MyClass parameter);
In a dynamically typed language there can be no such assurances. The best that can be done is to manually implement checks, but this is tedious and time consuming. Additionally, these checks will only occur at runtime, thus complicating the process of debugging.
Zope Interfaces can be used to enforce the implementation of all of the interface. That's why they were created.
Again, Zope interfaces force the developer to spend their time implementing checks to make sure that instance objects fully implement the interface their methods were designed to handle.
In the end, I suppose it is a matter of preference. Personally, I would rather place the burden of performing these tasks on the compiler.
That is a blatant distortion of history propagated by Mr. Rumsfeld himself. None of the recently declassified documents regarding the visit reflect this. Considering Mr. Rumsfeld's current lack of credibility, and highly creative use of rhetoric, this comes as no surprise.
The question is not if, but when, and why? In order to properly analyze the current situation in Iraq, one must have a greater historical perspective. If you investigate further you will enventually discover the paradox, and the blantant hypocrisy, of the current US administration. They were the ones who sold Iraq many of its chemical, biological, and conventional munitions. They turned a blind eye to the injustices Hussein exacted upon his people. They were complicit. The big question is: What guides their motivations now? They have yet to produce any hard evidence validating their initial premises for going to war (i.e. Weapons of Mass Destruction, and a link between Iraq, and Al Queda). Does this not concern you?
I wanted to comment about your response to this criticism in my original post, but I had forgotten my initial intentions for mentioning it in the first place. I have since remembered them:)
You can't just look at a function definition and know what type of parameters it contains.
You can write anything you want in the docstring. Nothing prevents you from writing:
""" str,int,int -> int """
You can use your scheme of utilizing comments (docstring?) for indicating what types should be passed to a function, but not necessarily what types are passed to a function. The difference is subtle, but significant, and in certain situations can create bugs that are very difficult to trace. As a programmer if means that you have to faith that the code calling a particular function will not pass incompatible types. In a "type-safe" language, such as Java, you can be assured that the compiler will let the developer know before he/she passes "classA" to a function expecting "classB".
Because all objects are created equal. The is no way of telling whether a particular class is really a descendent of the parent class the polymorphic expression was intended to act upon. This also ties in with my point about enforcing inheritance. When passing an object to a function there is no way to ensure that the instance is actually descended from the class the function was intended to handle.
You can't code to an interface, or abstract class.
Of course you can. Check out Zope's Interface, for example.
I didn't say you couldn't create an interface, or that that you couldn't write code to implement an interface. Again, the issue is one of enforcement. There is nothing in Python to prevent someone from implementing only half of an interface and trying to use it. This difficulty becomes apparent when utilizing large frameworks with very specific extension points.
In answer to your last question, I was using PHP at the time. I have not written code in Python; however, I will probably add it to my list of known languages eventually. I did do some research for these posts because I wanted to make sure the dynamic typing system works in a similar way to the one in PHP (my apologies if I missed anything).
"Dynamically typed object model scales incredibly well."
Sorry, no it doesn't. You can't overload functions. You can't use true polymorphism. You can't enforce inheritance. You can't code to an interface, or abstract class. You can't just look at a function definition and know what type of parameters it contains. You can't detect type-based errors until runtime. These are all the things that will slow you down in six months, and beyond. I've been there, and thats why I will never go back to a dynamically typed language for anything over 2,000 lines.
IANAL, but I have read a few contracts. If a contract has a clause regarding modification of the terms it usually refers to the specific party to which it applies. Example:
NewCo has to right to modify the terms set out in this agreement, at any time, without the knowledge or consent of The Customer.
Only 9,000? Try an estimated 37,000+ as a direct result of the conflict, and subsequent chaos. All for the false premise of alleviating the threat of Saddam Hussein's non-existant weapons of mass destruction. Where is the justice?
I agree. Reasoned argumentation is totally absent from this letter. Therefore, we can assume it was either written by Darl himself, or the PR department (which is currently populated by a troop of chimpanzees).
"'copy left'... is exactly opposite in its effect from the 'copy right' laws"
And how do you keep the journalists honest? How do you make sure they ask the tough questions, and get the answers they deserve? How do you ensure that they balance their reporting, and try to cover all aspects of a story from differing perspectives? Journalists, and media corporations are certainly afflicted by self-interest and ideology too. How can you trust them so completely?
After reading the letter, and looking through the exhibits it is evident that this particular Apache project has a systemic problem. In reading much of the preceding posts it would appear that many people equate this letter with the action taken by SCO, and are thus opposed to granting it any merit. On the contary, this is far from the opaque stance taken by the aforementioned SCO. The JBoss Group has shown specific instances of infringement, whereas SCO has not.
What many do not seem to understand, is that this specific instance is exactly the kind of enforcement, of open source licenses, we should be encouraging! If we are to take them at face value, the JBoss Group is merely trying to maintain the integrity of the intellectual property rights of its contributors. I see no reason to demonish them for that! Futhermore, it should also be noted they have not instigated or blatantly threatened legal action, this is also to their credit.
Even though some Americans would like to see Canada annexed, it has not happened yet! That being said, I sincerely doubt that anybody in Ontario will be handing their PINs over to the Democrat or Republican National Committees', or the American Green Party any time soon! Besides, this system is only being used for municipal elections, so no parties are involved.
Well after reading the article, and many of the posts, I have really mixed feelings. As a programmer, an aspect of my job is to reduce complexity for end users. On the other hand, I feel it is important for those users to become computer savvy.
It is absurd to suggest that most individuals require the depth of understanding that your typical software engineer must possess.
That said, I think being able to independently diagnose, understand, and solve computing related problems is becoming an essential skill. Another dimension of this is the ability to intuitively learn how to use unfamiliar software.
Currently, when things go slightly amiss or new software is introduced, many individuals will stare blankly at the screen, panic, and proceed to cry out for technical support. While in some cases it is quite useful to seek advice, most problems (often misunderstandings) are relatively trivial, and could have been solved had the person decided to experiment. This lack of initiative can usually be attributed to fear. Computers can be very intimidating, especially for people who have not grown up surrounded by them. I think this will change over time with the increasing prevalence of the technology.
Gee, sounds swell! I'd love to take SCO's money! Just one thing... Does it count if I dual boot? Then, when I feel like getting some more dough I can just switch to Windows, and when it starts to piss me off I can switch back. And, the best part is, I can do it again, and again, and again!!!
Slashdot Mirror
Don't take it the wrong way when she changes the subject. For some reason PhD students, at least the ones I know, hate to talk about their thesis.
Why was my comment modded Troll? Some people totally lack a sense of humor! My comment was tongue-and-cheek, yet at the same time pointed to convey scientific fact. Geez, makes me wonder...
I clone human cells all the time, my body does it for me, its called cell mitosis!
Mars!? You can't be serious! The sneaky devil might actually manage to survive...
Can you imagine what an upset it would be for the astronauts, when they arrive in 2030, only to find Darl suing the pants off the Martians? Just to be safe we had better send him off to Uranus!
If the United States institutes such a barbaric policy as a digital "lockdown", it would only have the effect of stifling technological innovation. This would be akin to committing economic suicide. A "zero-tolerance" policy for insecure software would sufficiently deter all but the wealthiest corporations from taking the risks associated with software development, but only in the US. The fear of accidentally introducing a defect, or vulnerability into a product would mean that the process of innovation itself becomes a liability. The lack of competitive pressure in the domestic market from smaller developers, would permit the larger software companies to slash research spending, in order to increase their profit margin; amid all of this they would become complacent. All of a sudden, software in the US would begin to look quite static when compared to the rest of the world (which by now is adopting Linux, and other OSS at an phenomenal rate). The gradual decrease in market share for US, in the software industry, becomes a flood. Pretty soon the US is behind the rest of the world in other sectors, as software in foreign countries becomes cheaper, faster, better and ironically, more secure.
Hmmmm.... Glowing bacteria? What would that be like?
If your definition of "whacko" includes someone with the training, discipline, fortitude, strength of mind and body, coupled with the shear will to survive the harsh conditions of Mars... Then I would place that kind of bet.
Given ten years to prepare, I would volunteer myself in an instant.
IANAL, so bear with me...
I'm not buying it either, and I agree with most of your assertions. In essence, the labels license music from an artist, and then sub-license it to consumers. The consumer can then make as many personal copies of the original as they like. The only stipulations relate to the distribution, broadcast, or public performance of the work in question. An artists royalties are proportional to the number of units sold (i.e. consumer licenses). Therefore, it would seem quite plausible that two copies of the same song could be construed as a single unit, provided they were sold to a one consumer as a single purchase item.
Read this.
That's not Polymorphism, it's plain old static typing.
It is highly related to polymorphism. Was my original criticism entirely lost on you? I said dynamic typed languages do not support "true" polymorphism, because - as you mentioned - any class can be valid with any expression provided it contains the requisite method! For instance, classes "ShapeA" and "ShapeB" could both contain the method area(), allowing for the seemingly proper execution of code, while failing to extend the anticipated "BaseShape".
They don't complicate debugging at all - you see the traceback on exception, and notice what line of code calls a method that doesn't exist. Such errors are trivial to correct, and are not really all that common either (usually typos)
In most cases I would agree with you, but only if you assume the developer writing code using the function:
1. Has perfect documentation, and never forgets to implement a rarely used, but critical method; or
2. Has the source code so the he can see how the function works so that he can make sure he hasn't forgotten to implement a method that is only called in certain circumstances; or
3. Tests all possible input
That's because usually these checks are not made at all in dynamically typed languages. They are simply not needed.
Actually, in many cases these checks need to be made, especially within the scope of framework or toolkit development (of which I do a considerable amount).
It's a tradeoff, really. Dynamically typed languages lose some, and win a lot.
The gains decrease exponentially with the size, and complexity of the project.
Believe me, I used to think the way you do now before discovering Python.
Well I'll certainly give it a try. Please understand that I really have no prejudice when it comes to languages; they all have advantages, and disadvantages. What I'm attempting to do is make observations based around issues that dynamically typed languages have in common.
I don't think you understood my point... In Java the compiler would check the following definition to ensure that all objects passed to myFunction are of type MyClass or descended from it:
In a dynamically typed language there can be no such assurances. The best that can be done is to manually implement checks, but this is tedious and time consuming. Additionally, these checks will only occur at runtime, thus complicating the process of debugging.
Zope Interfaces can be used to enforce the implementation of all of the interface. That's why they were created.
Again, Zope interfaces force the developer to spend their time implementing checks to make sure that instance objects fully implement the interface their methods were designed to handle.
In the end, I suppose it is a matter of preference. Personally, I would rather place the burden of performing these tasks on the compiler.
That is a blatant distortion of history propagated by Mr. Rumsfeld himself. None of the recently declassified documents regarding the visit reflect this. Considering Mr. Rumsfeld's current lack of credibility, and highly creative use of rhetoric, this comes as no surprise.
Oh, and so what if Rumsfeld went to Iraq?
The question is not if, but when, and why? In order to properly analyze the current situation in Iraq, one must have a greater historical perspective. If you investigate further you will enventually discover the paradox, and the blantant hypocrisy, of the current US administration. They were the ones who sold Iraq many of its chemical, biological, and conventional munitions. They turned a blind eye to the injustices Hussein exacted upon his people. They were complicit. The big question is: What guides their motivations now? They have yet to produce any hard evidence validating their initial premises for going to war (i.e. Weapons of Mass Destruction, and a link between Iraq, and Al Queda). Does this not concern you?
I wanted to comment about your response to this criticism in my original post, but I had forgotten my initial intentions for mentioning it in the first place. I have since remembered them :)
You can't just look at a function definition and know what type of parameters it contains.
You can write anything you want in the docstring. Nothing prevents you from writing:
""" str,int,int -> int """
You can use your scheme of utilizing comments (docstring?) for indicating what types should be passed to a function, but not necessarily what types are passed to a function. The difference is subtle, but significant, and in certain situations can create bugs that are very difficult to trace. As a programmer if means that you have to faith that the code calling a particular function will not pass incompatible types. In a "type-safe" language, such as Java, you can be assured that the compiler will let the developer know before he/she passes "classA" to a function expecting "classB".
You can't use true polymorphism.
How come?
Because all objects are created equal. The is no way of telling whether a particular class is really a descendent of the parent class the polymorphic expression was intended to act upon. This also ties in with my point about enforcing inheritance. When passing an object to a function there is no way to ensure that the instance is actually descended from the class the function was intended to handle.
You can't code to an interface, or abstract class.
Of course you can. Check out Zope's Interface, for example.
I didn't say you couldn't create an interface, or that that you couldn't write code to implement an interface. Again, the issue is one of enforcement. There is nothing in Python to prevent someone from implementing only half of an interface and trying to use it. This difficulty becomes apparent when utilizing large frameworks with very specific extension points.
In answer to your last question, I was using PHP at the time. I have not written code in Python; however, I will probably add it to my list of known languages eventually. I did do some research for these posts because I wanted to make sure the dynamic typing system works in a similar way to the one in PHP (my apologies if I missed anything).
"Dynamically typed object model scales incredibly well."
Sorry, no it doesn't. You can't overload functions. You can't use true polymorphism. You can't enforce inheritance. You can't code to an interface, or abstract class. You can't just look at a function definition and know what type of parameters it contains. You can't detect type-based errors until runtime. These are all the things that will slow you down in six months, and beyond. I've been there, and thats why I will never go back to a dynamically typed language for anything over 2,000 lines.
IANAL, but I have read a few contracts. If a contract has a clause regarding modification of the terms it usually refers to the specific party to which it applies. Example:
NewCo has to right to modify the terms set out in this agreement, at any time, without the knowledge or consent of The Customer.
Only 9,000? Try an estimated 37,000+ as a direct result of the conflict, and subsequent chaos. All for the false premise of alleviating the threat of Saddam Hussein's non-existant weapons of mass destruction. Where is the justice?
I agree. Reasoned argumentation is totally absent from this letter. Therefore, we can assume it was either written by Darl himself, or the PR department (which is currently populated by a troop of chimpanzees).
... is exactly opposite in its effect from the 'copy right' laws"
"'copy left'
Pure legal genius!!!
but what happens when you want to view a quicktime video? Or an AVI? Or watch a DVD? Or read an Excel document? Or...
I do all of these things routinely on my laptop, running under Linux... I guess you are somewhat misinformed.
And how do you keep the journalists honest? How do you make sure they ask the tough questions, and get the answers they deserve? How do you ensure that they balance their reporting, and try to cover all aspects of a story from differing perspectives? Journalists, and media corporations are certainly afflicted by self-interest and ideology too. How can you trust them so completely?
After reading the letter, and looking through the exhibits it is evident that this particular Apache project has a systemic problem. In reading much of the preceding posts it would appear that many people equate this letter with the action taken by SCO, and are thus opposed to granting it any merit. On the contary, this is far from the opaque stance taken by the aforementioned SCO. The JBoss Group has shown specific instances of infringement, whereas SCO has not.
What many do not seem to understand, is that this specific instance is exactly the kind of enforcement, of open source licenses, we should be encouraging! If we are to take them at face value, the JBoss Group is merely trying to maintain the integrity of the intellectual property rights of its contributors. I see no reason to demonish them for that! Futhermore, it should also be noted they have not instigated or blatantly threatened legal action, this is also to their credit.
Even though some Americans would like to see Canada annexed, it has not happened yet! That being said, I sincerely doubt that anybody in Ontario will be handing their PINs over to the Democrat or Republican National Committees', or the American Green Party any time soon! Besides, this system is only being used for municipal elections, so no parties are involved.
Well after reading the article, and many of the posts, I have really mixed feelings. As a programmer, an aspect of my job is to reduce complexity for end users. On the other hand, I feel it is important for those users to become computer savvy.
It is absurd to suggest that most individuals require the depth of understanding that your typical software engineer must possess. That said, I think being able to independently diagnose, understand, and solve computing related problems is becoming an essential skill. Another dimension of this is the ability to intuitively learn how to use unfamiliar software.
Currently, when things go slightly amiss or new software is introduced, many individuals will stare blankly at the screen, panic, and proceed to cry out for technical support. While in some cases it is quite useful to seek advice, most problems (often misunderstandings) are relatively trivial, and could have been solved had the person decided to experiment. This lack of initiative can usually be attributed to fear. Computers can be very intimidating, especially for people who have not grown up surrounded by them. I think this will change over time with the increasing prevalence of the technology.
Gee, sounds swell! I'd love to take SCO's money! Just one thing... Does it count if I dual boot? Then, when I feel like getting some more dough I can just switch to Windows, and when it starts to piss me off I can switch back. And, the best part is, I can do it again, and again, and again!!!