如果在Java中声明浮点数时需要'f'后缀,因为double是默认值,为什么当float是非小数时不使用'f'是可接受的?
float myFloat = 123.45 // not ok because double is the default
float myFloat = 123.45f // ok because the float is explicit
float myFloat = 123 // ok, but why? isn't it still a double by default?
Run Code Online (Sandbox Code Playgroud) 为什么视图中的某些实例变量没有“@”符号?这是 Rails 提供的一种便利,其中匹配控制器名称的实例变量可用,还是其他东西在这里起作用?
前任:
picks_controller.rb
@pick = Pick.new
@show = Show.new
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_form.html.erb
<%= pick.class %> // no exception raised
<%= show.class %> // "undefined local variable or method `show'" exception raised
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