擅长:python、mysql、java
<p>有些人选择了defaultDict</p>
<pre><code>greeting_dict = {'greetings': 'hello'}
if 'name' in greeting_dict :
opening_line = '{greetings} {name}'.format(**greeting_dict)
else:
opening_line = '{greetings}'.format(**greeting_dict)
print opening_line
</code></pre>
<p>也许更简洁的是,使用dictionary get设置每个参数的默认值</p>
<pre><code>'{greetings} {name}'.format(greetings=greeting_dict.get('greetings','hi'),
name=greeting_dict.get('name',''))
</code></pre>