Transfer practice · A function has an outer label "Workshop". Return {label="Visitor", outer="Workshop"} by using a separate local visitorLabel rather than replacing label.

Keep calculations in their own scope: practice

v3 · Activity 1 of 1 · scope · locals · 10 min Runs here

Chapter outline

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Mini-mission

Use a familiar idea in a different task. Read the changed requirement before running.

Your task

A function has an outer label "Workshop". Return {label="Visitor", outer="Workshop"} by using a separate local visitorLabel rather than replacing label.

Interface: calculate(base, bonus) -> {reward:number, reserve:number}

Input	Expected
Separate labels	`{ label = "Visitor", outer = "Workshop" }`

See another example

local total = 100
local function double(value)
    local total = value * 2
    return total
end
print(double(3))
print(total)
return double

The inner total is 6; the outer total remains 100. They are different locals despite the matching name.

Syntax in this activity

New syntax: nested local scope

Earlier ideas used here

functions
parameters
local-variables
dictionaries

Explain more

A local is visible in its lexical scope: the block where it is declared and nested blocks, after the declaration. A function parameter is local to that call.

A new local can shadow an outer name. Assigning without local can instead change an existing outer variable. Read the declaration, not just the identifier spelling.

Independent calculations should create their own temporary values. This also prevents one test call from contaminating a later call.

Explain this code

Select a word or symbol in this authored example. Your editor draft stays unchanged.

 reserve  100
  calculatebase, bonus
    reserve  base  bonus
      reward  reserve, reserve  reserve 

 calculate

Choose a highlighted part to see what it means.

Free experiment

This is a private experiment copy. It does not replace your answer or complete the activity.

These inputs apply when your scratchpad returns the function described by the activity interface.

Test different inputs

Font size Plain text

local total = 100
local function double(value)
    local total = value * 2
    return total
end
print(double(3))
print(total)
return double

Luau keyword highlighting · Ctrl/⌘ + Enter: Run · Esc: leave editorTab inserts indentation

Experiment Output

Your output will appear here.

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Code

Luau

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local label = "Workshop"
local function visitor()
    label = "Visitor"
    return { label = label, outer = label }
end
return visitor

Luau keyword highlighting · Ctrl/⌘ + Enter: Run · Esc: leave editorTab inserts indentation

Your output will appear here.

Ready

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Your task

A function has an outer label "Workshop". Return {label="Visitor", outer="Workshop"} by using a separate local visitorLabel rather than replacing label.

Interface: calculate(base, bonus) -> {reward:number, reserve:number}

Input	Expected
Separate labels	`{ label = "Visitor", outer = "Workshop" }`

See another example

local total = 100
local function double(value)
    local total = value * 2
    return total
end
print(double(3))
print(total)
return double

The inner total is 6; the outer total remains 100. They are different locals despite the matching name.

Syntax in this activity

New syntax: nested local scope

Earlier ideas used here

functions
parameters
local-variables
dictionaries

Explain more

A local is visible in its lexical scope: the block where it is declared and nested blocks, after the declaration. A function parameter is local to that call.

A new local can shadow an outer name. Assigning without local can instead change an existing outer variable. Read the declaration, not just the identifier spelling.

Independent calculations should create their own temporary values. This also prevents one test call from contaminating a later call.

Explain this code

Select a word or symbol in this authored example. Your editor draft stays unchanged.

 reserve  100
  calculatebase, bonus
    reserve  base  bonus
      reward  reserve, reserve  reserve 

 calculate

Choose a highlighted part to see what it means.

Free experiment

This is a private experiment copy. It does not replace your answer or complete the activity.

These inputs apply when your scratchpad returns the function described by the activity interface.

Test different inputs

Font size Plain text

local total = 100
local function double(value)
    local total = value * 2
    return total
end
print(double(3))
print(total)
return double

Luau keyword highlighting · Ctrl/⌘ + Enter: Run · Esc: leave editorTab inserts indentation

Experiment Output

Your output will appear here.