Home >Backend Development >Python Tutorial >python idle 解释和直接 python script.py 解释有什么差别?
<code class="language-python"><span class="err">$</span> <span class="n">python</span>
<span class="n">Python</span> <span class="mf">2.7</span><span class="o">.</span><span class="mi">5</span> <span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="n">Mar</span> <span class="mi">9</span> <span class="mi">2014</span><span class="p">,</span> <span class="mi">22</span><span class="p">:</span><span class="mi">15</span><span class="p">:</span><span class="mo">05</span><span class="p">)</span>
<span class="p">[</span><span class="n">GCC</span> <span class="mf">4.2</span><span class="o">.</span><span class="mi">1</span> <span class="n">Compatible</span> <span class="n">Apple</span> <span class="n">LLVM</span> <span class="mf">5.0</span> <span class="p">(</span><span class="n">clang</span><span class="o">-</span><span class="mf">500.0</span><span class="o">.</span><span class="mi">68</span><span class="p">)]</span> <span class="n">on</span> <span class="n">darwin</span>
<span class="n">Type</span> <span class="s">"help"</span><span class="p">,</span> <span class="s">"copyright"</span><span class="p">,</span> <span class="s">"credits"</span> <span class="ow">or</span> <span class="s">"license"</span> <span class="k">for</span> <span class="n">more</span> <span class="n">information</span><span class="o">.</span>
<span class="o">>>></span> <span class="n">a</span> <span class="o">=</span> <span class="mf">10.1</span>
<span class="o">>>></span> <span class="n">b</span> <span class="o">=</span> <span class="mf">10.1</span>
<span class="o">>>></span> <span class="n">a</span> <span class="ow">is</span> <span class="n">b</span>
<span class="bp">False</span>
<span class="o">>>></span> <span class="nb">id</span><span class="p">(</span><span class="n">a</span><span class="p">)</span>
<span class="mi">140475784803760</span>
<span class="o">>>></span> <span class="nb">id</span><span class="p">(</span><span class="n">b</span><span class="p">)</span>
<span class="mi">140475784803736</span>
<span class="o">>>></span> <span class="p">(</span><span class="mf">10.1</span><span class="p">)</span> <span class="ow">is</span> <span class="p">(</span><span class="mf">10.1</span><span class="p">)</span>
<span class="bp">True</span>
<span class="o">>>></span> <span class="k">def</span> <span class="nf">foo</span><span class="p">():</span>
<span class="o">...</span> <span class="n">a</span> <span class="o">=</span> <span class="mf">10.1</span>
<span class="o">...</span> <span class="n">b</span> <span class="o">=</span> <span class="mf">10.1</span>
<span class="o">...</span> <span class="k">return</span> <span class="n">a</span> <span class="ow">is</span> <span class="n">b</span>
<span class="o">...</span>
<span class="o">>>></span> <span class="n">foo</span><span class="p">()</span>
<span class="bp">True</span>
</code>
is 是判断identity的,如果两个变量 id (address)相同,那么a is b就是True;