Explicit return statement in Ruby - Step-by-Step Execution

Concept Flow - Explicit return statement

Start function

↓

Execute code lines

↓

Encounter return statement?

No→Continue executing

Yes↓

Return value immediately

↓

Exit function

The function starts and runs code until it finds a return statement, then it immediately sends back the value and stops running.

Execution Sample

Ruby

def greet(name)
  return "Hello, #{name}!"
  "This line is ignored"
end

puts greet("Alice")

This code defines a function that returns a greeting string immediately, ignoring any code after the return.

Execution Table

Step	Action	Code Line	Return Value	Notes
1	Function greet called with name='Alice'	def greet(name)		Function starts
2	Return statement executed	return "Hello, #{name}!"	"Hello, Alice!"	Function returns immediately
3	Code after return ignored	"This line is ignored"		Skipped
4	Function ends	end		Function exits with return value
5	puts outputs return value	puts greet("Alice")	Hello, Alice!	Output to console

💡 Return statement causes immediate exit from function with value "Hello, Alice!"

Variable Tracker

Variable	Start	After Step 1	After Step 2	Final
name	undefined	Alice	Alice	Alice
return_value	undefined	undefined	"Hello, Alice!"	"Hello, Alice!"

Key Moments - 2 Insights

Why does the line after the return statement not run?

Because the return statement immediately exits the function, so any code after it is skipped, as shown in execution_table row 3.

What value does the function send back when called?

The function returns the string "Hello, Alice!" right at the return statement, as seen in execution_table row 2.

Visual Quiz - 3 Questions

Look at the execution table, what is the return value at step 2?

A "Hello, Alice!"

B "This line is ignored"

C nil

D "Alice"

💡 Hint

Check the 'Return Value' column at step 2 in the execution_table.

At which step does the function stop running code inside it?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the 'Notes' column where it says the function returns immediately.

If we remove the return statement, what happens to the output?

A The function returns the first line's value

B The function returns nil

C The function returns the last line's value

D The function causes an error

💡 Hint

In Ruby, without explicit return, the last evaluated expression is returned.

Concept Snapshot

def function_name(params)
  return value  # Immediately exits function with value
  # Code after return is ignored
end

Use return to send back a value early from a function.

Full Transcript

This example shows how a Ruby function uses an explicit return statement. When the function greet is called with "Alice", it runs until it hits the return line. At that point, it immediately sends back the greeting string and stops running. Any code after return is ignored. The output is "Hello, Alice!" printed to the console. This teaches that return ends the function early and sends back a value.