Computer Science – 4.2 Assembly Language | e-Consult

Both indentation and curly braces {} are used to group instructions in programming, but they serve different purposes and are used in different languages. The choice between them is often a stylistic preference or a requirement of the language.

Indentation: Indentation is primarily used in languages like Python to define blocks of code. It relies on consistent spacing to indicate the scope of a block. Incorrect indentation will lead to syntax errors. Indentation is a visual cue to the structure of the code.

Curly Braces: Curly braces {} are used in languages like C++, Java, JavaScript, and C# to define blocks of code. They are part of the language's syntax and are required for correct parsing. Curly braces explicitly delineate the start and end of a block.

Example (Python):

def greet(name):
if name == "Alice":
print("Hello, Alice!")
print("Welcome to the program.")
else:
print("Hello, " + name + "!")

In this Python example, the two print statements inside the if block are grouped using indentation. The consistent indentation (usually four spaces) indicates that these statements belong to the if block. Incorrect indentation would result in a IndentationError.

Example (Java):

public class Main {
public static void main(String[] args) {
String name = "Bob";
if (name == "Alice") {
System.out.println("Hello, Alice!");
System.out.println("Welcome to the program.");
} else {
System.out.println("Hello, " + name + "!");
}
}
}

In this Java example, the two System.out.println statements inside the if block are grouped using curly braces {}. The curly braces explicitly define the block of code that is executed if the condition is true. Curly braces are a mandatory part of Java's syntax.

In summary, indentation is a stylistic and semantic tool in languages like Python, while curly braces are a syntactic requirement in languages like Java and C++ for defining code blocks.