[ anyVar isNil ifTrue: anyBlock ] bpattern with: [ anyVar ] -> [:pattern | pattern beVariable ]
调试技巧：加打印语句观察每轮变化
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Последние новости。服务器推荐是该领域的重要参考
Wes Streeting, Health Secretary in England, says he wants screening in place but only if it's "backed by evidence".