Server Side Programming Articles - Page 2567 of 2650

In C++, tokens, identifiers, and keywords all are fundamental elements of a program. Tokens are the smallest units of code which are combine together to form complete program, where both keywords and identifiers are the types of tokens. The keywords are reserved words in the language, where each provides separate meanings to code and cannot be used as names by the programmer, whereas identifiers are names defined and used by programmers to represent variables, function or other user-defined elements. In this article, we will learn about all three in detail. Tokens in C++ A token is the smallest element of ... Read More

A token is the smallest element of a C++ program that is meaningful to the compiler. The C++ parser recognizes these kinds of tokens: identifiers, keywords, literals, operators, punctuators, and other separators. A stream of these tokens makes up a translation unit. Tokens are usually separated by white space.The parser recognizes keywords, identifiers, literals, operators, and punctuators. Preprocessing tokens(like #include, #define, #if_def, etc.) are used in the preprocessing phases to generate the token stream passed to the compiler. The preprocessing token categories are header names, identifiers, preprocessing numbers, character literals, string literals, etc. that do not match one of the ... Read More

Yes, In C++ both const and volatile keywords can be applied together in a variable. But it is used in situations like a read-only hardware register, or an output of another thread. In C++, they both are type qualifiers, which are used for different purposes in programming. In this article we will see the use of both keywords in C++. const Keyword The const keyword is used to declare the value of a variable as constant, meaning its value cannot be changed or modified later once initialized with const keyword. Example In this example PI value is set as constant ... Read More

In C++, both #define and const are used to define constants in a program. The #define is a preprocessor directive that creates macros with their fixed values whereas const is a keyword which declare value of variable as constant, meaning its value cannot be changed after intialization. Therefore they have different use cases in different scenarios. In this article, we will learn the differences between these two in detail. #define in C++ The #define is a preprocessor directive that is used to define or assign macros ( name or string ) with a constant value. So wherever the macro occurs ... Read More

The const keyword in C++ is a keyword that is used to declare variables and objects as constant, which means the value declared using const cannot be changed or modified later, once they are initialized. This helps them prevent accidental modifications. For example, in a code, if we are using the value of PI, which has a fixed universal value and doesn't need any change, then we can declare it as a constant. When you declare the object with the const keyword, then the compiler places that value in ROM (Read-Only Memory), which protects it from being changed ... Read More

The #define creates a macro, which is the association of an identifier or parameterized identifier with a token string. After the macro is defined, the compiler can substitute the token string for each occurrence of the identifier in the source file.#define identifier token-stringThis is how the preprocessor is used. The #define directive causes the compiler to substitute token-string for each occurrence of identifier in the source file. The identifier is replaced only when it forms a token. That is, identifier is not replaced if it appears in a comment, in a string, or as part of a longer identifier.example#include #define ... Read More

Yes! We can use a pass statement in a Python if clause. This is used when a statement is required syntactically, but you do not want any command or code to execute. It represents a piece of code that will be added later, but initially, a placeholder is required to ensure the program runs without errors. And the if statement in Python evaluates whether a condition is true or false. So, the pass statement can be used in an if as well as an else block. Pass Statement in If Clause In this section, we will see ... Read More

In Python, in and not in operators are called membership operators. Their purpose is to check if an object is a member of a certain sequence object like string, list, or tuple. The not in operator returns false if object is present in sequence, true if not found>>> 'p' not in 'Tutorialspoint' False >>> 'c' not in 'Tutorialspoint' True >>> 10 not in range(0,5)

The "is" operator in Python is an identity operator. This operator checks whether two variables refer to the same object in memory. It returns boolean values as a result. Each object in the computer's memory is assigned a unique identification number (id) by the Python interpreter. Identity operators check if the id() of two objects is the same. The 'is' operator returns false if id() values are different and true if they are the same. Syntax of Python (is) Operator The "is" operator follows the following syntax in Python: variable1 is variable2 The "is" operator ... Read More

In some languages like C / C++ the "!" symbol is used as a logical NOT operator. !x it returns true if x is false else returns false. The equivalent of this "!" operator in python is logical NOT, It also returns true if the operand is false and vice versa. Example In the Following example the variable operand_X holds a boolean value True, after applying the not operator it returns False. operand_X = True print("Input: ", operand_X) result = not(operand_X) print('Result: ', result) Output Input: True Result: False Example For False value the ... Read More