debug statement

基本解释

To debug such a problem, it's important to know what the value of the variable is, using a print() or a die() statement.
要调试这类问题，重要的是用 print() 或 die() 语句知道变量的值是什么。
Every time you consider writing a debug printout, consider writing a unit-test instead. ( or turn int into logging statement)
用单元测试或者记录日志来代替测试时的输出。
Note that this is a little more advanced than a typical HelloWorld application that prints the statement without user interaction, but the message is printed to debug.
注意，这比只打印出 hello world 句子而没有用户交互的典型 HelloWorld 应用程序稍高级一些，但消息被输出到了调试窗口。