<p>您的代码有一个有趣的事实,就是它会在其背后寻找值来检测更改。不幸的是,最后一个值没有机会被检测到,因为循环到此结束</p>
<hr/>
<p>而是使用两个指针,一个用于当前&;一个用于列表中的下一个值。使用类似这样的条件来检测下一步中的更改(<strong>向前看</strong>)</p>
<pre class="lang-py prettyprint-override"><code>for index, outer in enumerate(outer_list):
next_outer_source = outer_list[index + 1] if index < len(outer_list) - 1 else None
show_outer_header = current_outer_name != outer.name or current_outer_source != outer.source
show_inner_values = next_outer_source is None or outer.name != next_outer_source.name or outer.source != next_outer_source.source
</code></pre>
<hr/>
<p>这是您的函数的一份清理副本:</p>
<pre class="lang-py prettyprint-override"><code>
def loop_over(outer_list, inner_list):
current_outer_name = None
current_outer_source = None
current_inner_name = None
current_inner_source = None
prev_outer_source = None
for index, outer in enumerate(outer_list):
next_outer_source = outer_list[index + 1] if index < len(outer_list) - 1 else None
show_outer_header = current_outer_name != outer.name or current_outer_source != outer.source
show_inner_values = next_outer_source is None or outer.name != next_outer_source.name or outer.source != next_outer_source.source
# print outer header
if show_outer_header:
print('\n{} ({})'.format(outer.name, outer.source))
print('=' * 15)
current_outer_name, current_outer_source = outer.name, outer.source
# print outer value
print('* [{}]: . "{}"'.format(outer.thing, outer.description))
# print inner values
if show_inner_values:
current_outer_name = outer.name
current_outer_source = outer.source
for inner in [x for x in inner_list if x.name == current_outer_name and x.source == current_outer_source]:
if current_inner_name is None:
print('\n{} ({})'.format(inner.in_name, inner.in_source))
print('-' * 15)
current_inner_name = inner.in_name
current_inner_source = inner.in_source
if inner.in_name != current_inner_name or inner.in_source != current_inner_source:
print('\n{} ({})'.format(inner.in_name, inner.in_source))
print('-' * 15)
current_inner_name = inner.in_name
current_inner_source = inner.in_source
print('* [{}]: . "{}"'.format(inner.thing, inner.description))
</code></pre>
<p>输出:</p>
<pre class="lang-sh prettyprint-override"><code>name1 (source1)
===============
* [name1-foo1]: . "description1"
* [name1-foo2]: . "description2"
* [name1-foo3]: . "description3"
subname1 (subsource1)
-
* [name1-sub1-bar1]: . "description1"
* [name1-sub1-bar2]: . "description2"
* [name1-sub1-bar3]: . "description3"
subname2 (subsource1)
-
* [name1-sub2-bar1]: . "description1"
* [name1-sub2-bar2]: . "description2"
* [name1-sub2-bar3]: . "description3"
name2 (source1)
===============
* [name2-foo1]: . "description1"
* [name2-foo2]: . "description2"
* [name2-foo3]: . "description3"
subname3 (subsource1)
-
* [name2-sub3-bar1]: . "description1"
* [name2-sub3-bar2]: . "description2"
* [name2-sub3-bar2]: . "description3"
name3 (source1)
===============
* [name3-foo1]: . "description1"
* [name3-foo2]: . "description2"
subname4 (subsource1)
-
* [name3-sub4-bar1]: . "description1"
* [name3-sub4-bar2]: . "description2"
* [name3-sub4-bar2]: . "description3"
subname5 (subsource1)
-
* [name3-sub5-bar1]: . "description1"
* [name3-sub5-bar2]: . "description2"
* [name3-sub5-bar3]: . "description3"
subname6 (subsource1)
-
* [name3-sub6-bar1]: . "description1"
* [name3-sub6-bar2]: . "description2"
* [name3-sub6-bar3]: . "description3"
</code></pre>