public static final function pack(array $Source, string $separator): array {
		return array_walk($Source, function(&$value, $key) use ($separator){
			$value = $key . $separator . Str::cast($value); }) ? array_values($Source) : [];
	}
public static final function pack(array $Source, string $separator): array {
		return array_walk($Source, function(&$value, $key) use ($separator){
			$value = $key . $separator . Str::cast($value); }) ? array_values($Source) : [];
	}
public static final function pack ( array $ Source , string $ separator ) : array { return array_walk ( $ Source , function ( & $ value , $ key ) use ( $ separator ) { $ value = $ key . $ separator . Str :: cast ( $ value ) ; } ) ? array_values ( $ Source ) : [ ] ; }
Returns an array contains string elements formed by a key-value pair
of the source array combined by the specified separator.

@attention Keys not preserved.

@attention This method throws an exception if any element
of the given array cannot be represented as a string.

@param array $Source
@param string $separator
@return array;
Returns an array contains string elements formed by a key - value pair of the source array combined by the specified separator .