1. @yuya_takeyama

5. Domain Specific
Languages
(Martin Fowler)

17. [
"foo",
"bar",
"hoge" => "piyo"
]

18. array(3) {
[0]=>
string(3) "foo"
[1]=>
string(3) "bar"
["hoge"]=>
string(4) "piyo"
}

21. public $id = array(
'type' => 'int',
'primary' => true,
'serial' => true
);
public $name = array(
'type' =>'string',
'required' => true,
'unique' => true
);
public $birthday = array(
'type' => 'date');

22. public $id = [
'int',
'primary' => true,
'serial' => true
];
public $name = [
'string',
'required' => true,
'unique' => true
];
public $birthday = ['date'];

25. ['begin',
['define',
'fib',
['lambda',
['x'],
['if',
['<', ':x', 2],
':x',
['+',
['fib', ['-', ':x', 2]],
['fib', ['-', ':x', 1]]]]]],
['print', 'fib(10) = '],
['println', ['fib', 10]]]
=> fib(10) = 55