Fundamentals of lambda expressions

Syntax Elements

Lambda Operator (->)

Divides the lambda expression into two parts:

Left side: Parameter list.

Right side: Lambda body (actions or return).

• Lambda Body Types:

Single expression: Directly returns the result of an expression.

Code block: Contains multiple instructions.

Examples of Lambda Expressions:

1) No parameters:

Example: () -> 98.6

• Empty parameter list.

• Returns a constant value 98.6 (type inferred as double).

• Equivalent to method:
  double myMeth() {
  return 98.6;
  }

Example: () -> Math.random() * 100

• Returns a pseudorandom number multiplied by 100.

2) With parameters:

Example: (n) -> 1.0 / n

• Returns the reciprocal of n.

• Parameter type usually inferred, but may be declared explicitly.

3) Return of Boolean values:

Example: (n) -> (n % 2) == 0

• Returns true if n is even, false otherwise.

• Simplified form (without parentheses in the parameter):
  n -> (n % 2) == 0.

Considerations

• The return type of a lambda expression is automatically inferred.

• Parentheses in parameters are optional for lambda expressions with a single parameter.

• The book suggests using parentheses for consistency in style.

General Summary

• The lambda expression simplifies the creation of anonymous methods.

• Flexible in terms of parameters and return types.

• Adopts a concise syntax to improve code readability and expressiveness.

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