我是編程的初學者,我試圖完成Zed Shaw的Ruby書,而我無法理解代碼的最後一個for
聲明。如果變量state
和abbrev
尚未定義,軟件如何知道從哪裏獲取值?Ruby用於使用未定義變量的語句
states = {
'Oregon' => 'OR',
'Florida' => 'FL',
'California' => 'CA',
'New York' => 'NY',
'Michigan' => 'MI'
}
cities = {
'CA' => 'San Francisco',
'MI' => 'Detroit',
'FL' => 'Jacksonville'
}
for state, abbrev in states
puts "%s state is abbreviated %s and has city %s" % [
state, abbrev, cities[abbrev]]
end
謝謝你的回答!我現在更清楚了:) – Amir