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Idiom #281 Use a Point as a map key

You have a Point with integer coordinates x and y. Create a map m with key type Point (or equivalent) and value type string. Insert "Hello" at position (42, 5).

Point = Struct.new(:x, :y)
m = {Point.new(42, 5) => "Hello"}
import "dart:math";
Map<Point, String> m = {};
m[Point(42, 5)] = "Hello";

m := map[Point]string{}
p := Point{x: 42, y: 5}
m[p] = "Hello"
import qualified Data.Map.Strict as Map
type Point = (Integer, Integer)
m :: Map.Map Point String
m = Map.empty
m' = Map.insert (42, 5) "Hello" m
import java.util.HashMap;
import java.util.Map;
Map<Point, String> m = new HashMap<>();
m.put(new Point(42, 5), "Hello");
use strict;
my %m;
my $p = Point->new(x => 42, y => 5);

$m{$p} = 'Hello';

m = dict()
p = Point(x=42, y=5)
m[p] = 'Hello'
from collections import namedtuple
Point = namedtuple('Point', 'x y')

p = Point(42, 5)

m = {p: "Hello"}
m = {Point(42, 5): 'Hello'}
use std::collections::HashMap;
let mut map: HashMap<Point, String> = HashMap::new();
map.insert(Point { x: 42, y: 5 }, "Hello".into());
New implementation...
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programming-idioms.org 
Point = Struct.new(:x, :y)
m = {Point.new(42, 5) => "Hello"}
Map<Point, String> m = {};
m[Point(42, 5)] = "Hello";

m := map[Point]string{}
p := Point{x: 42, y: 5}
m[p] = "Hello"
type Point = (Integer, Integer)
m :: Map.Map Point String
m = Map.empty
m' = Map.insert (42, 5) "Hello" m
Map<Point, String> m = new HashMap<>();
m.put(new Point(42, 5), "Hello");
my %m;
my $p = Point->new(x => 42, y => 5);

$m{$p} = 'Hello';

m = dict()
p = Point(x=42, y=5)
m[p] = 'Hello'
Point = namedtuple('Point', 'x y')

p = Point(42, 5)

m = {p: "Hello"}
m = {Point(42, 5): 'Hello'}
let mut map: HashMap<Point, String> = HashMap::new();
map.insert(Point { x: 42, y: 5 }, "Hello".into());