Control structures are a key computing concept found in virtually every piece of software ever written. Any real-world software controls the logical flow of the program execution, and this is done by using control structures (loops, conditionals, branching statements, and others). Control structures let a program move from just logically flowing from the first statement to the last one, to one which can skip, loop back to the start, branch out at different decision points (hence, create decision points), and much more. Essentially, programmers learn to control the logical flow of the software to make sure the software behaves exactly as intended in all expected (and, as required, unexpected) conditions, virtually eliminating any logical errors.
Along with control structures, logical and relational operators let the program make decisions and comparisons to create really precise (i.e., perfect) conditional statements (which create decision points in a program). Every programmer thus uses logical operators (AND, OR, NOT, and more) and relational operators (equal to, greater than, less than, and so forth) many times throughout a program. Therefore, the problem is not that these are complicated to understand; rather, the problem (i.e., what the bugs really represent) is really with applying these perfectly each time.
Consequently, my task here is to help! This article provides a simple set of summary points on what bugs to look for in every Go code. Examination of some excellent decision-making code samples will provide the required how-to information that will help you become a master of decision points! And this will lead to better-optimized Go code. Your code will be in better shape, which will translate into massive maintenance savings this same time next year.
Advanced Control Structures
If you want your code to be more efficient, more readable, and generally, you will have to use advanced control structures such as the switch and conditional operator (?:).
Switch control structures allow you to select specific code for multiple conditions, so you don’t have to use an if statement. If there was no switch statement you would have to use if-then-else statements, and depending on how many possible values there are for a variable, that could be a lot!
The conditional operator (also known as the ternary operator) allows you to provide three expressions (two of them must be the same type) and let the operator decide which one should be executed (think of it as a very compact if-else statement)
Also, the ternary operator will often allow your code to run quicker than an if-else structure. This specific type of if-else to ternary operator strategy should be used when you want an assignment and else if you just want a return value. If there’s a condition that chooses one of two possible values to return, one strategy is to use the conditional operator. Will it make your program run faster? No, but it improves the look of your code and could improve the speed a little, which means a lot in some embedded applications.
Selection Structures in Programming
Programming includes selection structures at its core—statements that allow a choice to be made.
The first level of selection structure is the plain, old, one-way if statement. If it’s raining, then I will open my umbrella. If it is dark, then I’ll turn on the light. (But not: open my code editor!) The one-way if is used in coding all the time.
If name = adrian then the system will return my email address, for example. But what if the name field is not adrian? In this case, I do not care what the result may be—it can be ignored.
This is a one-way if scenario. Just test for one thing. If it’s true, do something. If it’s not true, do nothing. It goes to the heart of the need to test everything even in a simple login form:
if username = George Weasley if password = Fred access authorised – launch system else wrong user id or password end Any code will have myriad examples of this structure.
The full, two-way if…else selection statement allows the program to test for some condition and then take one of two courses, as described above.
Next, the program can move on logically to create complex decision trees, particularly where the first decision is more or less binary then the initial outcome opens up multiple further choices.
For example: suppose the logic is enrollment for a new service equals old customers, only. But the conditions are:
If age > 18 if UK resident if income > £60,000 (for a hypothetical)
Then the logic is clear. The two-way if will cover this adequately, but the overall structure is complex even though the separate branches are simply true or false outcomes.
Utilizing Pseudocode for Development
Pseudocode serves as a false, or pseudo, line of code that we as developers can use to map out how our program will run.
Instead of worrying about what programming language to use, what the syntax of that language is, and how to handle computationally intense operations, pseudocode allows developers to write out their solutions in a step-by-step format.
By focusing more on translating human thoughts into a detailed explanation (i.e., here is the problem → develop a solution to the problem), the implementation becomes the last thing you have to worry about.
Something interesting about pseudocode is that when you write it, you don’t have to focus on large pieces of the problem. You just focus on the problem-solving aspect → what loops do I need, do I need to use a conditional.
Once the pseudocode is written, then and only then should you have to worry about the correct syntax and which language to use. Variations of pseudocode can exist from one person to another, however, teams can generally agree on what should and should not be included and the syntax for it.
This can be a great way to slow down, stop and think about what syntax is needed, and write out how you think your solution will need to run.
Pseudocode plays a big role in helping developers create software programs. We’re huge on software testing its importance. Pseudocode is essentially just writing out test cases! Many agree that developers should write test cases first–in fact, a large part of our Testing and Debugging course discusses this. So write your test cases, implement your program, and verify your program passes all of the intended test cases provided!
Test cases can be written in text file or .txt format, in a given Microsoft Word, or .doc and .docx, format, etc. Just as there are a variety of ways to solve a problem, there is an equal, if not greater, number of formats for writing testing cases.
But what about time and space complexity? QTest complies the currently used programming language (C++, sometimes Java and C#) by using Google’s C++ Testing Framework.
Evaluating Logical (Boolean) Expressions
Building and evaluating logical expressions is at the heart of programming and computer science.
Logical expressions often mix several types of data, such as integers (int), boolean values (bool), and strings. Different types of data offer other logical “moves.” To give some examples, boolean values are used directly in logical operations. Still, integers have different “logical moves” (i.e., a non-zero value is treated as true when evaluating conditions). Strings also have a “logical interpretation” in Python, for specific contexts (e.g., empty strings).
A term often heard regarding logical expressions is “short-circuit evaluation,” a colloquial term from electronics. In logical expressions, there is a well-known sequence of evaluations in operations involving AND (&&) and OR (||) operators. However, why bother evaluating the second operand in an AND operation if the first operand has been evaluated as false? After all, to evaluate one operand as false is enough to tell how the logical condition works out in total. Short-circuiting evaluations significantly cuts time and memory costs of evaluation. Just as important, the following, though, is the cause of substantial errors in the execution of the code. Division by zero? Access to null? TouchableOpacity?
The third issue is that it also affects the representation of code for established expressions. Experienced programmers utilize the knowledge about “short-circuit evaluation” in the running of their “logical capers.” For example, running of successive tests with a null-ed pointer. It helps immensely. Knowing it might also make some evaluations and assumptions they make seem true. The following code then becomes “trash.” At least they think, but you don’t have to.
Understanding Control Structures
Control structures are absolutely crucial elements of programming. They form the construct that glues a set of instructions together. So, they determine how a program will execute its instructions. There are three types of programming structures, and they include the following:
Selection Structure: The structure that lets a program make decisions on certain conditions.
Iteration Structure: The structure which allows a program to loop through code blocks multiple times
Sequence Structure: The default structure. All programming languages support this structure.
Logical and Relational Operators
Programming works with logical operators such as AND, OR, and NOT. These operators allow you to make complicated decisions by combining many conditions in your program. When you use the operator AND, for example, all separate conditions must be true for the whole expression to be true. On the other hand (no pun intended) the operator OR checks that at least one condition in the program is true. The operator NOT reverses a boolean expression (e.g., if the expression is true, NOT will return false).
Another type of operator, relational operators – ==, !=, <, > – simply compare decision values and ascertain if a particular condition is true or not. It is at this point in your code that you make a decision and also take an action. For example, you can check that a user has entered a sensible name and password: if the password is more than a certain length, you can ask the user to try again or to provide a valid password or keep using the program until you enter a length of an acceptable value.
It is far from always that comparing two conditions – AND and OR – results in code that acts predictably. If you write decision routines you should write code – with parentheses around each separate condition – such that another coder coming later will be in no doubt to what you intended, or that is legally inaccurate, or even that anyone can justifiably interpret.
Avoiding Bugs in Programming
Common simple bugs in programming come from a misunderstanding of control structures. In particular, the difference between equality (==) and assignment (=) can lead to many logical errors. Because these logical errors do not usually result in error messages (i.e., syntax errors), the problem can often be difficult to trace: An example can be if you use one equals sign when you should have used two; this would assign certain values to variables and make the program act in different (sometimes unpredictable) ways. These types of errors underscore the need to understand (i.e., be able to use and read) the syntax and semantics of the particular programming language.
To decrease the number of bugs, you might want to create a set of best practices (how-tos) that other developers should follow. For example:
Clearly state what each structure is supposed to do in a comment.
Use and keep consistent formatting styles.
Use descriptive variable names.
Programming skills start with the ability to understand how to use control structures and logical operators.
A developer controls program flow with control structures. These can be conditionals that cause code to execute if some condition is true (or false), which starts to bring some vitality to a program. This is almost always combined with the ability to display content that was not hard-wired into the program (such as displaying a result to a user). Without understanding control structures, a developer is pretty much lost. A developer will be lost without understanding how to use logical operators.
Programs drop into complex control structures and string together an eclectic series of true/false validations. Understanding control structures and logical operators, without a lot of practice, is an exercise in futility.
Practice ultimately becomes quantity: high-quality code generally results from copious amounts of practice that serve some but a few functions; to help identify bad coding before it actually happens -seeing and identifying emerging patterns is again, without a lot of practice or experience- generally considered a major bn.
+ There are no comments
Add yours