Nested conditions in Rust - Step-by-Step Execution

Concept Flow - Nested conditions

Start

↓

Check Condition A

↓

Check Condition B

↓

Execute inner block

↓

End

The program first checks an outer condition. If true, it checks an inner condition. Depending on inner condition, it executes different blocks. If outer condition is false, it executes the else block or ends.

Execution Sample

Rust

fn main() {
    let x = 10;
    if x > 5 {
        if x < 15 {
            println!("x is between 6 and 14");
        }
    }
}

Checks if x is greater than 5, then if x is less than 15, and prints a message if both are true.

Execution Table

Step	Condition Checked	Condition Result	Branch Taken	Output
1	x > 5	true	Enter first if
2	x < 15	true	Enter nested if	x is between 6 and 14
3	End of nested if	-	-
4	End of first if	-	-
5	Program ends	-	-

💡 All conditions evaluated; program ends after printing message.

Variable Tracker

Variable	Start	After Step 1	After Step 2	Final
x	10	10	10	10

Key Moments - 2 Insights

Why does the inner if only run if the outer if is true?

Because the inner if is inside the outer if block, it only executes when the outer condition is true, as shown in steps 1 and 2 of the execution_table.

What happens if the outer condition is false?

The program skips the inner if completely and does not print anything, as the branch taken at step 1 would be 'No' and no further steps inside the if run.

Visual Quiz - 3 Questions

Look at the execution_table, what is the result of the condition 'x > 5' at step 1?

A true

B false

C undefined

D error

💡 Hint

Check the 'Condition Result' column at step 1 in the execution_table.

At which step does the program print 'x is between 6 and 14'?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the 'Output' column in the execution_table for the print statement.

If x was 4, how would the execution_table change at step 1?

A Condition Result would be true

B Branch Taken would be 'Enter first if'

C Condition Result would be false

D Output would be printed

💡 Hint

Refer to the 'Condition Result' and 'Branch Taken' columns at step 1 in the execution_table.

Concept Snapshot

Nested conditions in Rust:
Use if inside another if to check multiple conditions.
Inner if runs only if outer if is true.
Syntax:
if condition1 {
    if condition2 {
        // code
    }
}
Useful to check layered conditions clearly.

Full Transcript

This example shows nested conditions in Rust. First, the program checks if x is greater than 5. If true, it then checks if x is less than 15. If both are true, it prints a message. The execution_table traces each step: checking the outer condition, then the inner condition, and printing the output. The variable_tracker shows x remains 10 throughout. Key moments clarify that the inner if only runs if the outer if is true, and if the outer condition is false, the inner block is skipped. The visual quiz tests understanding of condition results and output timing. Nested conditions help check multiple related conditions step-by-step.