2025-09-10:仓库迁移

4.迭代器与生成器/8.跳过可迭代对象中的前一部分元素.py

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+from itertools import dropwhile, islice
+
+if __name__ == '__main__':
+    words = ["#look", "#into", "#my", "eyes", "look", "into", "my", "eyes",
+              "the", "eyes", "the", "eyes", "the", "eyes", "not", "around", "the",
+              "eyes", "don't", "look", "around", "the", "eyes", "look", "into",
+              "my", "eyes", "you're", "under"]
+
+    # 想要对可迭代对象进行过滤，也可以使用dropwhile函数,比如这里我想过滤掉前几行有#的东西
+    for i in dropwhile(lambda x : x.startswith('#'), words):
+        print(i)
+
+    # dropwhile会在迭代时对函数进行匹配，将符合条件的值丢弃，直到出现第一个符合条件的值后停止工作返回所有剩余内容
+
+    # 如果你知道需要跳过几个元素，那可以直接用islice进行切片操作来过滤
+
+    items = ['a', 'b', 'c', 1, 2, 3]
+    # None表示[3:]
+    for i in islice(items, 3, None):
+        print(i)
+
+    # 当然，使用列表的过滤方法也可以删除一些不要的东西，但是这样的删除是全局的，而不是仅在开头生效