将javascript array.map转换为php array_map

Question

This is a javascript code that consists of hashmap array(keys:value).I created one function using map that returns values of entered keys.

var rule = 
{
"c": "d",
"a": "o",
"t": "g",
"h": "a",
"e": "n",
"n": "t"
}
function convert(str) {
return [...str].map(d => rule[d]).join('')
}
console.log(convert("cat"))
//prints dog

Now I want to convert above javascript code in php so that i can run it under php server. I created same array in php as

$rule = 
{
"c" => "d",
"a" => "o",
"t" => "g",
"h" => "a",
"e" => "n",
"n" => "t"
}

Using array_map,how to convert in php code in same way as done in javascript. Php syntax for array_map is

array_map(myfunction,array1,array2...)

Answer 1

Such function exists in php

echo strtr('cat', $rule);

demo

EDIT:

To do with array_map

echo join('', array_map(function($x) use($rule) { return $rule[$x]; }, str_split('cat')));

demo