Code Grammar — Chapter 1

How to write functions and What NOT to do!

What are functions?

Functions are the first line of organization in any program. In programming, a function is a self-contained block of code that performs a specific task or a set of tasks. Functions are designed to be reusable, which means they can be called multiple times from different parts of a program.

Structure of any function

The structure of a typical function in a programming language involves several components:

• function name
• parameters (if any)
• and the code block that contains the instructions

Best practices to follow

1. Size:

• The first rule of function is they should be small, and the second is they should be smaller in that.

2. Blocks and Indentation:

• Blocks within if , else, try,catchstatement and within loops should be one line, that line should be a function call probably.

3. Purpose:

• The function should do ONE thing.
• The function should either do something or answer something, but not both.

4. Level Abstraction

• If a function is doing one thing, then statements should all be at the same level of abstraction.
• Follow Step Down rule, the Step Down to Lower-Level Abstractions. The main function or method should provide a high-level overview of what it does, and as you move through the code, the details and complexity should gradually increase in a step-down fashion.

5. Naming

• The function name should be a verb.
• The name should describe what a function does, Long descriptive name is better than a short enigmatic one.

6. Function Argument

• Zero is the ideal no of arguments, More than two arguments should require justification.
• It becomes harder to test all combinations of arguments via unit test, in case of more arguments.
• Output arguments should not be avoided.
• Passing a boolean argument is not an ideal practice.
• The name should tell the order and intent of the arguments.

Special Case — Lambda functions

Lambda functions, also known as anonymous functions or lambda expressions, serve a specific purpose in programming. Lambda functions provide a concise way to define small, one-time-use functions without the need for a full function definition.

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Best Practices for Writing Lambda Functions:

• Lambda functions are meant for simple operations. Avoid complex logic within a lambda.
• For complex logic or critical code, regular functions are generally more testable and maintainable.
• Avoid nesting lambda functions excessively.
• Lambda functions work well with higher-order functions like map, filter, and reduce.