C#, Dart, TypeScript , Python: side-by-side

String formating

Each of these methods has its own advantages and use cases. For example, C#'s interpolated strings and Python's f-strings provide a very readable way to embed expressions in strings, while C#'s composite formatting is useful for more complex scenarios where you might want to reuse the same variable multiple times in a formatted string or apply specific formatting to values (like date or number formats).

It's important to note that these are not the only ways to format strings in these languages, but they are the most common and idiomatic methods

Ternary Conditional Operator

In Python, the ternary conditional operator is slightly different in syntax. It uses the if ... else keywords in a single line, rather than the ? and : symbols. The general form is x = true_value if condition else false_value.

In all these languages, the ternary conditional operator is used to make the code more concise and to reduce the need for a multi-line if-else statement when only a single value assignment is needed based on a condition.

Code Blocks

C#, Dart, TypeScript: In these languages, a code block begins with an opening curly brace { and ends with a closing curly brace }. Everything within the braces is considered part of the same block. For example:

// C# example
if (condition)
{
    // This is a code block
    Console.WriteLine("Condition is true.");
}

// Dart example
if (condition) {
  // This is a code block
  print('Condition is true.');
}

// TypeScript example
if (condition) {
    // This is a code block
    console.log("Condition is true.");
}

Python: Python uses indentation to define the beginning and end of a code block. The amount of indentation for each block is consistent, and typically four spaces are used per indentation level. For example:

# Python example
if condition:
    # This is a code block
    print("Condition is true.")

Enforced by Language: The enforcement of curly braces or indentation is a syntactic requirement in these languages. In C#, Dart, and TypeScript, omitting curly braces for code blocks that require them will result in a compiler error. In Python, inconsistent indentation will lead to a syntax error.

Readability: While not enforced by the compiler or interpreter in C#, Dart, and TypeScript, indentation is still crucial for maintaining readable and maintainable code. It is considered a best practice to use consistent indentation, such as using spaces or tabs, to visually separate code blocks from the surrounding code.

Loops

For Loop

For-Each Loop

While Loop

Do-While Loop

Loop Control Statements

Notes on Loop Usage

C#, Dart, TypeScript: These languages share a similar C-style syntax for loops, including the traditional for loop with initialization, condition, and increment expressions. They also support for-each loops for iterating over collections, with slight differences in keyword usage (foreach in C# and for in Dart and TypeScript).

Python: Python's for loop is more like a for-each loop in C-style languages, iterating over items in a collection or sequence. Python uses the range() function to iterate over a sequence of numbers. Python does not have a traditional C-style for loop or a do-while loop.

Do-While Loop: Python does not have a built-in do-while loop construct. However, you can achieve similar behavior using a while loop with a condition that is always true initially, followed by a conditional break at the end of the loop body.

Loop Control Statements: The break statement is used to exit a loop prematurely, while the continue statement is used to skip the current iteration and proceed to the next iteration of the loop. These control statements are used similarly across all four languages.

Anonymous and Higher-Order Functions

Anonymous Functions (Lambdas)

Higher-Order Functions

Notes on Anonymous Functions and Higher-Order Functions

C# uses lambda expressions to create anonymous functions and has a variety of higher-order functions available through LINQ (Language Integrated Query), such as Select, Where, and Aggregate.

Dart supports arrow syntax for defining anonymous functions concisely. Higher-order functions like map, where, and reduce are commonly used on collections.

TypeScript, like Dart, uses arrow functions for concise anonymous function syntax. It also has higher-order functions on arrays similar to Dart and other JavaScript array methods.

Python uses the lambda keyword to define anonymous functions. It has built-in higher-order functions like map, filter, and reduce (the latter is found in the functools module).

Object-Oriented Programming

Here are some key points about OOP in each language:

C#: C# is a statically typed language with a rich set of OOP features. It supports most of the classical OOP concepts, including interfaces, abstract classes, encapsulation with access modifiers, and polymorphism through virtual and override methods. C# does not support multiple inheritance for classes, but it allows a class to implement multiple interfaces.

Dart: Dart is an object-oriented language that supports classes and interface-like behavior using abstract classes. Unlike C#, Dart does not have interfaces as a separate construct; instead, every class implicitly defines an interface. Dart does not support method overloading but does support operator overloading. It uses a single underscore to denote private members.

TypeScript: TypeScript is a superset of JavaScript that adds static typing and OOP features. It supports classes, interfaces, and inheritance. TypeScript's OOP features are similar to those of C#, but since it compiles down to JavaScript, which is a prototype-based language, some features like operator overloading are not natively supported.

Python: Python is a dynamically typed language that supports OOP. It allows for multiple inheritance and uses a special module called abc (Abstract Base Classes) to create abstract classes and methods. Python does not have built-in access modifiers, but it follows a naming convention using underscores to indicate the intended level of privacy. Method overloading is not natively supported, but operator overloading is.