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Programming-Idioms

# 8 Create a map (associative array)
Create a new map object x, and provide some (key, value) pairs as initial content.
New implementation

Be concise.

Be useful.

All contributions dictatorially edited by webmasters to match personal tastes.

Please do not paste any copyright violating material.

Please try to avoid dependencies to third-party libraries and frameworks.

Other implementations 
with Ada.Containers.Indefinite_Hashed_Maps;
with Ada.Strings.Hash;

use Ada.Containers;
declare
   package Maps is new Indefinite_Hashed_Maps (Key_Type => String,
                                               Element_Type => Integer,
                                               Hash => Ada.Strings.Hash,
                                               Equivalent_Keys => "=");
      
   use Maps;
      
   X : Map := Empty_Map;
begin
   X.Insert ("One", 1);
   X.Insert ("Two", 2);
   X.Insert ("Three", 3);
end;
#include <search.h>
ENTRY a = {"foo", "twenty"};
ENTRY b = {"bar", "three"};
if (hcreate (23)) {
    hsearch(a, ENTER);
    hsearch(b, ENTER);
}
module StringMap = Map.Make(String)

let x =
    StringMap.empty
    |> StringMap.add "one" 1
    |> StringMap.add "two" 2
    |> StringMap.add "three" 3
(def x {"One" 1
	"Two" 2
	"Three" 3})
#include <map>
using namespace std;
pair a { 'x', 1 },
     b { 'y', 2 };
map m { a, b };
#include <map>
std::map<const char*, int> x;
x["one"] = 1;
x["two"] = 2;
#include <map>
using namespace std;
map<char, int> m {
    { 'x', 1 },
    { 'y', 2 }
};
#include <unordered_map>
std::unordered_map<std::string, double> mymap = {
    {"mom", 5.4},
    {"dad", 6.1},
    {"bro", 5.9}
};
using System.Collections.Generic;
var x = new Dictionary<string, int> {
   ["year"] = 2019,
   ["month"] = 12
};
using System.Collections.Generic;
var x = new Dictionary<string, int> {
   {"year", 2019}, {"month", 12}
};
int[string] x = ["one": 1, "two": 2];
var x = {
	"one": 1,
	"two": 2
};
x = %{"one" => 1, "two" => 2}
x = %{one: 1, two: 2}
X = #{one => 1, "two" => 2.0, <<"three">> => [i, i, i]}.
x := map[string]int {"one": 1, "two": 2}
def x = [un:1, dos:2, tres:3]
def x = ['un':1, 'dos':2, 'tres':3]
import Data.Map.Strict
x = Data.Map.Strict.fromList [ ("red", "FF0000"), ("blue", "0000FF") ]


const x = new Map();
x.set("one", 1);
x.set("two", 2);
const x = {one: 1, two:2}
const x = new Map([["one",1],["two",2]]);
import java.util.Map;
import java.util.HashMap;
Map<String,Integer> x = new HashMap<>();
x.put("one", 1);
x.put("two", 2);
import java.util.Map;
import java.util.HashMap;
final Map<String, Integer> x = new HashMap<String, Integer>() {{
    put("one", 1);
    put("two", 2);
    put("three", 3);
}};
import static java.util.Map.of;
import java.util.HashMap;
import java.util.Map;
Map<String, Integer> x = new HashMap<>(of("x", 1, "y", 2));
import static java.util.Map.of;
import java.util.Map;
Map<String, Integer> x = of("x", 1, "y", 2);
import static java.util.Map.entry;
import static java.util.Map.ofEntries;
import java.util.Map;
import java.util.Map.Entry;
Entry<String, Integer> a = entry("x", 1),
                       b = entry("y", 2);
Map<String, Integer> x = ofEntries(a, b);
val x = mutableMapOf<String, Int>().apply { 
    this["one"] = 1
    this["two"] = 2
}
val x = mutableMapOf<String, Int>()
x["one"] = 1
x["two"] = 2
val x = mapOf("one" to 1, "two" to 2)

(let ((table (make-hash-table)))
  (setf (gethash 'one table) 1)
  (setf	(gethash 'two table) 2))
x = {one = 1, two = 2}
NSDictionary *x=@{@"one":@1, @"two":@2};
$x = ['one' => 1, 'two' => 2];
uses fgl;
type TMap = specialize TFPGMap<String, Integer>;
var x: TMap;

begin
  x := TMap.Create;
  x['one'] := 1;
  x['two'] := 2;  
end.

my %x = ( 
    name => 'Roboticus',
    'foo bar' => 'joe'
);
x = {"one" : 1, "two" : 2}
class DefaultMap(dict):
    def __init__(self, *args, **kwargs):
        kwargs = {'x': 1, 'y': 2} | kwargs
        super().__init__(args, **kwargs)
x = DefaultMap(z=3)
keys = 'abc'
values = 1, 2, 3
x = dict(zip(keys, values))
x = {}
x['a'] = 1
x['b'] = 2
x['c'] = 3
x = dict(a=1, b=2, c=3)
x = {one: 1, two: 2}
use std::collections::HashMap;
let x: HashMap<&str, i32> = [
    ("one", 1),
    ("two", 2),
].into_iter().collect();
use std::collections::BTreeMap;
let mut x = BTreeMap::new();
x.insert("one", 1);
x.insert("two", 2);
val x = Map("a" -> 1, "b" -> 2, "c" -> 3)
(define x '(
    ("one" 1) 
    ("two" 2) 
    ("three" 3)))
x := Dictionary newFrom: {
	#a -> 1.
	#b -> Object new}.
Imports System.Collections.Generic
Dim x As New Dictionary(Of String, Integer)() From {
    {"one", 1},
    {"two", 2}
}

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