memoize_example.php

function busy_work( $value ) {
  $sha256 = partially_apply( 'hash', 'sha256' );
  $retval = $value;
  for( $i = 0; $i < 1000; $i++ ) {
    $retval = $sha256( $retval );
  }
  
  return $retval;
}

$memoized_hash = memoize( 'busy_work' );
$hash_value_1 = $memoized_hash( 'sha256', 'Hello World' ); // 0.0058081150054932us
$hash_value_2 = $memoized_hash( 'sha256', 'Hello World' ); // 0.0010941028594971us