Enums

Enums are a fundamental feature in Rust that let you define a type that can be one of several distinct variants. Enums make it easier to represent a set of related states or options cleanly and effectively.

In this challenge, you will implement a simple TrafficLight enum to represent the states of a traffic light: Red, Yellow, and Green. Each variant will be a unit struct with no associated data.

Your Task

Create an enum TrafficLight with three variants:

Red representing the red light.
Yellow representing the yellow light.
Green representing the green light.

Write a function light_action that takes a TrafficLight and returns a string describing the action associated with the light.

For Red, return "Stop".
For Yellow, return "Caution".
For Green, return "Go".

Hints

Click here to reveal hints

Use the match statement to handle each enum variant.

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Solutions

LouisMareschal

2 hours ago

3.50ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    let output:&str;
    match light{
        TrafficLight::Red => output = "Stop",
        TrafficLight::Yellow => output = "Caution",
        TrafficLight::Green => output = "Go",
    }
    return output;
}

wertion555

13 hours ago

3.13ms

81.28kb

pub enum TrafficLight {
    Red, Yellow, Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light{
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Javets70

13 hours ago

3.31ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light{
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Noxyss

18 hours ago

2.78ms

81.28kb

#[derive(Eq, PartialEq)]
pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    if *light == TrafficLight::Red {
        return "Stop"
    } else if *light == TrafficLight::Yellow {
        return "Caution"
    }
    return "Go"
}

Harsh Ranjan

harshRn

20 hours ago

3.12ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

bernardoLY19

a day ago

2.76ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light{
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go" ,
    }
}

Baron Curtin

baroncurtin2

2 days ago

3.06ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

xvzhang

xvzhnang

3 days ago

2.87ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Cobran53

4 days ago

2.90ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

YVV

yvv4git

5 days ago

4.14ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Jai

jsat97

5 days ago

2.98ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

virvid

6 days ago

3.16ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

alexsavio

6 days ago

2.80ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

baschdik

8 days ago

2.81ms

81.28kb

pub enum TrafficLight {
    Red, 
    Yellow,
    Green, 
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

coreyralph

8 days ago

2.90ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

medzernik

8 days ago

2.71ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Herman effendi

hrmneffdii

8 days ago

2.74ms

81.28kb

#[derive(PartialEq)]
pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    if *light == TrafficLight::Red {
        return "Stop";
    } else if *light == TrafficLight::Yellow {
        return "Caution";
    } else {
        return "Go"
    }
}

Artem Nistuley

artemnistuley

8 days ago

2.68ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Miguel Ángel Allende

maallende

10 days ago

3.06ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

CDzungx

11 days ago

2.96ms

81.28kb

pub enum TrafficLight {
    Red,
    Green,
    Yellow
}
pub fn light_action(light: &TrafficLight) -> &'static str {
   match light{
    TrafficLight::Red => {"Stop"}
    TrafficLight::Yellow => {"Caution"}
    TrafficLight::Green => {"Go"}
   }
}

Philippe Massicotte

PMassicotte

11 days ago

2.98ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Ushakov Andrey

stdstring

11 days ago

3.39ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

kcoolio

chrisjude254

11 days ago

2.68ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red, 
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    return match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution", 
        TrafficLight::Green => "Go"
    };
}

vanos001

12 days ago

2.73ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    return match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    };
}

Enes

enesscevik

13 days ago

2.99ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match *light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Camiam144

13 days ago

4.71ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light{
        TrafficLight::Red => return "Stop",
        TrafficLight::Yellow => return "Caution",
        TrafficLight::Green => return "Go"
    }
}

KuuShyn

13 days ago

4.01ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Luigi Terrone

LuigiTer

14 days ago

2.74ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Karol Płatkowski

spoohie

15 days ago

8.33ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Heino Mortensen

hmortensen83

15 days ago

3.26ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

0x0f1

Paul4673

15 days ago

2.97ms

81.28kb

pub enum TrafficLight {
    Red, Yellow, Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

noomcreator

16 days ago

2.80ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

dattruongdev

16 days ago

3.84ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red, 
    Yellow, 
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Kr0wZ

17 days ago

3.23ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

silaskoemen

18 days ago

2.86ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Tri Nguyen

nguyentri

18 days ago

2.89ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Sarthak Mishra

sithtsar

18 days ago

3.06ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red, 
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    let a: &'static str = match light{
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green  => "Go",
    };
    a
}

xxxxsk

20 days ago

2.75ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Pierre Gordo

PierreGordo

21 days ago

3.58ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red, 
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light{
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Gomathi Shankar

gomathishankar37

21 days ago

3.84ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

Satya Sundar Sahu

satya200

21 days ago

4.74ms

81.28kb

#[derive(PartialEq)]
pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    if *light == TrafficLight::Red {
        "Stop".as_ref()
    }
    else if *light == TrafficLight::Yellow {
        "Caution".as_ref()
    }
    else {
        "Go".as_ref()
    }
}

abelneo

abel-cod

22 days ago

3.54ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => return "Stop",
        TrafficLight::Yellow => return "Caution",
        TrafficLight::Green => return "Go", 
    }
}

Lucop1911

22 days ago

3.35ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Rocky.C

cloki0610

22 days ago

4.90ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

Tommy

verse215

22 days ago

3.58ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

hahu07

23 days ago

3.62ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light{ 
    TrafficLight::Red => "Stop",
    TrafficLight::Yellow => "Caution",
    TrafficLight::Green => "Go"
     }
}

s.i

ssmi75

24 days ago

2.68ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red, Yellow, Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go"
    }
}

ikatlinsky

25 days ago

2.96ms

81.28kb

pub enum TrafficLight {
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}

zzispp

25 days ago

2.74ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
     Red,
     Yellow,
     Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light{
        TrafficLight::Red=> "Stop",
        TrafficLight::Yellow=>"Caution",
        TrafficLight::Green=> "Go",
    }
}

Tim

timvyy

a month ago

2.76ms

81.28kb

pub enum TrafficLight {
    // Define enum variants here
    Red,
    Yellow,
    Green,
}
pub fn light_action(light: &TrafficLight) -> &'static str {
    // Your code here...
    match light {
        TrafficLight::Red => "Stop",
        TrafficLight::Yellow => "Caution",
        TrafficLight::Green => "Go",
    }
}