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Programming-Idioms

# 13 Iterate over map keys and values
Access each key k with its value x from an associative array mymap, and print them.
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;
for C in My_Map.Iterate loop
   Put_Line ("Key = " & Key (C) & ", Value = " & Element (C));
end loop;
(doseq [[k x] mymap]
  (println k ":" x))

#include <iostream>
for (auto entry : mymap) {
  auto k = entry.first;
  auto x = entry.second;
  std::cout << k << ": " << x << "\n";
}
#include <cstdio>
for (auto& [k, x] : mymap)
    printf("%s %s\n", k, x);
#include <iostream>
for (const auto& [k, x]: mymap) {
	std::cout << "Key: " << k << " Value: " << x << '\n';
}
#include <map>
K k;
X x;
auto i {mymap.begin()}, n {mymap.end()};
while (i not_eq n) {
    k = i->first;
    x = i->second;
    printf("%s %s\n", k, x);
    ++i;
}
#include <iostream>
for (const auto& kx: mymap) {
	std::cout << "Key: " << kx.first << " Value: " << kx.second << std::endl;
}
foreach(var entry in map)
{
    Console.WriteLine("Key=" + entry.Key + ", Value=" + entry.Value);
}
import std.stdio;
int[string] mymap = ["Hello":1 , "World":2];
foreach (k, v; mymap)
    writeln("Key: ", k, " Value: ", v);
mymap.forEach((k, v) => print('Key=$k, Value=$v'));
Enum.each(mymap, fn({k, x}) ->
  IO.puts("#{k} => #{x}")
end)
for {k, x} <- mymap do
  IO.puts("#{k} => #{x}")
end
maps:fold(
	fun(K, V, ok) ->
		io:format("~p: ~p~n", [K, V])
	end, ok, MyMap).
import "fmt"
for k, x := range mymap {
  fmt.Println("Key =", k, ", Value =", x)
}
mymap.each { k, x ->
	println "Key $k - Value $x"
}
import Data.List (intercalate)
import qualified Data.Map as Map
let f k v = [show k, " = ", show v]
    mapped = Map.mapWithKeys f mymap
in putStrLn $ intercalate "," $ mapped
Object.entries(mymap).forEach(([key, value]) => {
	console.log('key:', key, 'value:', value);
});

for (const key in mymap) {
    console.log('key:', key, 'value:', mymap[key]);
}
import java.util.Map;
mymap.forEach((k,x) -> System.out.println("Key=" + k + ", Value=" + x));
for (Map.Entry<Object, Object> entry : mymap.entrySet()) {
    Object k = entry.getKey();
    Object x = entry.getValue();
    System.out.println("Key=" + k + ", Value=" + x);
}
import static java.lang.System.out;
import java.util.Map.Entry;
K k;
X x;
for (Entry<K, X> e : mymap.entrySet()) {
    k = e.getKey();
    x = e.getValue();
    out.println(e);
}
mymap.forEach { k, v -> println("$k -> $v") }
mymap.entries.forEach { print("${it.key} ${it.value}") }
(loop for k being each hash-key of mymap
      for x being each hash-value of mymap                                                                            
      do (format t "~A ~A~%" k x)))
for k, x in pairs(mymap) do
	print('Key: '..k..', Value: '..x)
end
@import Foundation;
for (NSString *k in mymap)
  NSLog(@"Key %@, value %@",k,mymap[k]);
foreach ($mymap as $k=>$x)
{
    echo "Key=$k, Value=$x <br>";
}
uses fgl;
type TMyMap = specialize TFPGMap<String, Integer>;
for i := 1 to mymap.Count 		do
  WriteLn(mymap.Keys[i], '=', mymap.Data[i]);
printf "Key=%s, Value=%s\n",$_,$mymap{$_} foreach (sort keys %mymap);


while (my ($k, $x) = each %mymap) {
    print "Key=$k, Value=$x\n";
}
forall(get_dict(K, D, V),
       format("~w:~w~n", [K, V]))
for k, v in mymap.items():
    print(k, v)
for x in mymap.items():
    print(x)
mymap.each {|k, x| puts "Key= #{k}  Value=#{x}"}
use std::collections::BTreeMap;
for (k, x) in &mymap {
    println!("Key={key}, Value={val}", key=k, val=x);
}
val x = Map("a" -> 1, "b" -> 2, "c" -> 3)
x.foreach{ case (key, value) => println(s"$key => $value")}
mymap.foreach { case (k, x) => println(s"$k => $x") }
mymap keysAndValuesDo: [ :k :x |
	Transcript cr;
		show: 'Key = ', k printString;
		show: ', Value = ', x printString]

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