word-choiceword-differenceword-meaningword-usage
Which one is correct and making proper sense, Else is there any major difference between the two.
That code should be debuggable.
That code should be able to debug.
If there is no difference in the meaning. What will be the proper place to use each of the above.
Your understanding of the word "would" is wrong. When talking about future events the difference between "will" is referring to something that is going to happen in the real world, but "would" is talking about what would happen in a hypothetical situation. So for example, I could say
I would go skiing with you if I had the money.
and that means that if I had more money (an imaginary situation) then I would go with you. Let's take another sentence.
I would go skiing with you if I could get a day off of work.
This means that I have given up trying to get a day off, and I don't think it's possible. In a hypothetical where I do get off work, I would go with you, but in the real world I will not. However, if I say
I will go skiing with you if I can get a day off of work.
that means that I don't know if I can get a day off or not. I'm still trying to convince my boss to let me have a day off, and I don't know if he will let me or not. If he does, I will go with you, but if he doesn't, I will not.
But what if I want to say "It will not happen?" Because the meaning of "it will not happen" is that something is that is unlikely or, worse still, not going to happen, shouldn't it be more accurate to say "it would not happen"?
If I say "It will not happen", it does not mean it is unlikely. It means "In the future, this event is going to not happen." "It would not happen" is only accurate if you're talking about a hypothetical.
Now onto your last sentence:
"I think you will not be able to do it" or "I think you would not be able to do it".
It all depends on the context.
Let's say that I want to run a marathon. I sign up, and start training. The big day comes and I'm really excited. You want to discourage me so you say:
I think you will not be able to finish the race.
New scenario: Let's pretend that I've always wanted to run a marathon, but I am afraid of failing. I want to try, but I want to know that I can finish the race before I make an attempt. I come up to you and ask, "Do you think that I could run a marathon?" You want to discourage me so you say:
I think you would not be able to finish the race.
The two words you have chosen to define are particularly difficult to pin a definition to. If you were to ask this question on the Philosophy Stack Exchange you could get references to thousands upon thousands of pages of philosophy on the concepts. That philosophical basis helps shape the meanings of the words, so it is very hard to define them without at least touching on philosophy.
As such, you will find my wording choices waver, even in this answer. While it seems natural that the two words might have clearcut definitions, in reality the truth is that people mix their meanings all the time. (Forgive me, I know that sentence construction was cruel and unusual)
I believe the trick to understanding the words is that, when you use them to refer to a statement within language, the line between the words is murky. Accordingly, I'll explore their differences first, and then we'll bring them together.
Truth is typically considered an abstract concept. It doesn't "exist" anywhere, unless you have a religious belief which can point to a truth in reality. 1+1=2 is true, even though 1+1=2 is an abstract concept. We might argue that you can demonstrate its truth using real objects in reality, such as taking one stone and putting it next to another stone, and calling that "two stones." However, as we go deeper into mathematics, we find truths which are increasingly difficult to argue are part of "reality." For instance, a2 + b2 = c2 when referring to the side lengths of a right triangle is a true statement, even if one never constructs a physical triangle in reality. In fact, we can make true statements about really unusual mathematical concepts that can never be physical such as Graham's number such as "the last 6 digits of Graham's number are 195387," even though Graham's number is so mindbogglingly big that it is actually impossible to write down directly in reality (the number is so much larger than the number of atoms in the universe that it actually hurts).
On the other side of the argument, it is possible for things to be "real" but not "true," and at this point I'll start trying to do comparative pairs of sentences to help try to explain the difference. A "real" thing is not considered "true" until it is assigned a truth value. People, for example, are typically not assigned a truth value. If I were to talk about an individual in history named Jesus, I would say "Jesus was real" or "Jesus was not real." I would not say X"Jesus is true" or X"Jesus is false," except in the most informal of ways (some will use the questionable construction "Jesus is true/false" as a shortcut for saying "The abstract content of Jesus's message is true/false," just showing once again how murky the line is).
The two words get very very very similar when discussing statements. Statements we have made span the gap between the abstractness of truth and the concreteness of reality. I don't believe I can do this topic justice in a SE answer. The way those words bob and weave within the context of statements is something you'll just have to learn on your own. Fortunately, in that narrow context English speakers will be willing to accept both constructions with little to no confusion.
One of the more interesting lines that gets drawn between the words is the idea that truth can be conditional, but there is only one reality. This is an assumption made in the vast majority of English speaking countries. I can make a statement about the truth-hood of a mathematical proposition within some defined bounds: "It is true that water brings life (truth statement), assuming it does not drown it first (context)." In that sentence, I was able to use the word "true" in a conditional sense. I cannot do that with reality, on the assumption that there is only one reality. This behavior can be seen in a compound statement, "It is true that water brings life, assuming it does not drown it first. However, in reality, the dam upstream is about to burst, and it will drown us if we stay here."
And, frustratingly, the story doesn't end there. The words continue to dance in a strange loop. Because the concept of "in reality" got so over used, we started to question the assumption that there is only one reality. We developed constructions using the phrase "my reality" or "your reality," and typically they are used with the assumption of one "truth!" Gads! Thus you will come across statements like, "Maybe in your reality you can act any way you like, but in truth, there's only one way to live."
And so, I believe I have given you lots of information, but its unclear whether it has actually helped. The best advice for understanding them I can give, in context of all I have written, is to use "true" when dealing with abstract concepts, and "reality" when dealing with concrete physical concepts. In the murky region inbetween, use context: determine if the current conversation suggests "one reality," which is the default for most English speakers, or if it suggests "one truth," and then use your words accordingly.
Best Answer
These two are actually very different.
This one is fine - this is the correct and natural way to say what you're trying to say.
This one made me laugh a little bit, because I'm pretty sure you didn't intend to write this. Plus I wish what you wrote actually existed. It would make things a lot easier for me.
So what you actually wrote here is that your code should have the ability to debug. In other words, you wrote some sort of intelligent AI that is able to debug other code. Man, that'd be amazing. Definitely not what you meant though.
What you were probably looking for was this
Now that is grammatically sound, however it is not ever said this way because the structure is needlessly complicated.
Stick with the first choice for practically all uses. They have equivalent meaning, but in my experience, the first choice is much more common.