原文地址：
YAML是一种旨在直接可由人类编写和读取的数据序列化语言。
它是JSON的严格超集，语法上添加了类似Python的换行符和缩进。 但是与Python不同，YAML不允许使用TAB缩进。
--- # 文档开始# 这是注释########### 标量类型 ########### 我们的根对象（包含整个文档）是一个map，# 等价于其他语言中的dictionary, hash 或 objectkey: value # 键值对another_key: Another value goes here. # 另一个键值对a_number_value: 100 # 数值scientific_notation: 1e+12 # 科学计数法表示的数值boolean: true # 布尔值null_value: null # null值key with spaces: value # 带空格的键# 注意字符串不需要引号，但可以使用引号however: 'A string, enclosed in quotes.' # 用引号括起来的字符串'Keys can be quoted too.': "Useful if you want to put a ':' in your key." # 键也可以括起来single quotes: 'have ''one'' escape pattern' # 使用单引号double quotes: "have many: \", \0, \t, \u263A, \x0d\x0a == \r\n, and more." # 使用双引号# 多行字符串可以采用“文本块” （使用 |）,# 或“折叠块”（使用 >）literal_block: | This entire block of text will be the value of the 'literal_block' key, with line breaks being preserved. The literal continues until de-dented, and the leading indentation is stripped. Any lines that are 'more-indented' keep the rest of their indentation - these lines will be indented by 4 spaces.# 整个文本块将是'literal_block'键的值，保留换行符。# 直到进一步缩进时，所有前导缩进将会被去除。# 存在“更多缩进”的行将保留其缩进的剩余部分 - 这两行好将缩进4个空格。# # 示例结果：# This entire block of text will be the value of the 'literal_block' key,# with line breaks being preserved.# # The literal continues until de-dented, and the leading indentation is# stripped.# # Any lines that are 'more-indented' keep the rest of their indentation -# these lines will be indented by 4 spaces.folded_style: > This entire block of text will be the value of 'folded_style', but this time, all newlines will be replaced with a single space. Blank lines, like above, are converted to a newline character. 'More-indented' lines keep their newlines, too - this text will appear over two lines.# 折叠风格可以将（空格分割的）长行在空格处打断为多行，其特点是：# - 折叠的换行符替换为空格# - 更多缩进的行不折叠# （译者注：这里，以及官方文档，都没能将其规则说清楚，为什么空行消失。但一般不会遇到这么复杂的字符串，所以不用深究。）# ## 示例结果：# This entire block of text will be the value of 'folded_style', but this time, all newlines will be replaced with a single space.# Blank lines, like above, are converted to a newline character.# # 'More-indented' lines keep their newlines, too -# this text will appear over two lines.########### 集合类型 ############ 使用缩进嵌套，推荐2个空格（但非必须）a_nested_map: key: value another_key: Another Value another_nested_map: hello: hello# map不一定需要字符串的键0.25: a float key# 键可以很复杂，如多行对象。# 使用 ? 及其后的一个空格，表明复杂键的开始? | This is a key that has multiple lines: and this is its value# YAML同样允许序列之间映射，使用复杂键的语法。# 一些实现不支持这样做，如jackson。? - Manchester United - Real Madrid: [2001-01-01, 2002-02-02]# 序列（等价于列表或数组）如下所示# （注意'-'记作一个缩进）:a_sequence: - Item 1 - Item 2 - 0.5 # 序列支持不同类型 - Item 4 - key: value another_key: another_value - - This is a sequence - inside another sequence - - - Nested sequence indicators - can be collapsed# 鉴于YAML是JSON的超集，可以使用JSON风格的map和序列：json_map: {"key": "value"}json_seq: [3, 2, 1, "takeoff"]and quotes are optional: {key: [3, 2, 1, takeoff]}############额外的功能 ############ YAML拥有称为“锚”的便捷功能，可以在文档中复用内容。下两个key拥有共同的值：anchored_content: &anchor_name This string will appear as the value of two keys.other_anchor: *anchor_name# 锚可用于复制/继承属性base: &base name: Everyone has same name# The regexp << is called Merge Key Language-Independent Type. It is used to# indicate that all the keys of one or more specified maps should be inserted# into the current map.foo: &foo <<: *base age: 10bar: &bar <<: *base age: 20# foo and bar would also have name: Everyone has same name# YAML还有标记，您可以使用它来显式声明类型。explicit_string: !!str 0.5# Some parsers implement language specific tags, like this one for Python's# complex number type.python_complex_number: !!python/complex 1+2j# We can also use yaml complex keys with language specific tags? !!python/tuple [5, 7]: Fifty Seven# Would be {(5, 7): 'Fifty Seven'} in Python################# 额外的YAML类型 ################## 除了字符串和数字值，YAML还支持ISO格式的date和datetime字面量。datetime: 2001-12-15T02:59:43.1Zdatetime_with_spaces: 2001-12-14 21:59:43.10 -5date: 2002-12-14# "!!binary"标签声明一个字符串是base64编码的，表示一个二进制blob# （译者注：参考Python相关概念）gif_file: !!binary | R0lGODlhDAAMAIQAAP//9/X17unp5WZmZgAAAOfn515eXvPz7Y6OjuDg4J+fn5 OTk6enp56enmlpaWNjY6Ojo4SEhP/++f/++f/++f/++f/++f/++f/++f/++f/+ +f/++f/++f/++f/++f/++SH+Dk1hZGUgd2l0aCBHSU1QACwAAAAADAAMAAAFLC AgjoEwnuNAFOhpEMTRiggcz4BNJHrv/zCFcLiwMWYNG84BwwEeECcgggoBADs=# YAML拥有一个集合类型：set: ? item1 ? item2 ? item3or: {item1, item2, item3}# 集合只是简单的映射为空值，以上等价于：set2: item1: null item2: null item3: null... # 文档结束