What is the behavior of Kotlin's smart cast when used inside an if statement that checks a variable's type?

easy📝 Conceptual Q1 of 15

Kotlin - Control Flow as Expressions

What is the behavior of Kotlin's smart cast when used inside an if statement that checks a variable's type?

AThe variable is automatically cast to the checked type within the <code>if</code> block.

BThe variable must be explicitly cast using <code>as</code> inside the <code>if</code> block.

CThe variable's type remains unchanged and cannot be used as the checked type.

DThe variable is cast only if it is declared as <code>val</code> outside the <code>if</code> block.

Step-by-Step Solution

Solution:

Step 1: Understand smart cast
Kotlin automatically casts a variable to the checked type inside an if block when the type is verified.
Step 2: Check variable mutability
This works only if the variable is immutable (val) or not modified between the check and usage.
Final Answer:
The variable is automatically cast to the checked type within the if block. -> Option A
Quick Check:
Smart cast applies automatically inside if after type check [OK]

Quick Trick: Smart casts auto-cast after type checks in if blocks [OK]

Common Mistakes:

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