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<p class="MsoNormal">Years ago, I fell in love with python and left C an C++ behind. Sometime later, I fell in love with C# because with strong typing, my IDE does most of the work for me - I never have to browse the API to find which method or attribute exists
in a class, I can use tab completion for everything, avoid type-o's, etc. So I was recently thrilled to discover type hinting in python, and support included in pycharm. I'm coming back to python now (for the last few months).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In python 3.6.1, and pycharm CE 2017.1.1 on windows (I haven't tested other versions or other platforms):<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The following is recognized and supported by pycharm, but then at runtime, python throws an exception:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> #!/usr/bin/env python3<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> def foo(bars: list[str]):<o:p></o:p></p>
<p class="MsoNormal"> for bar in bars:<o:p></o:p></p>
<p class="MsoNormal"> if bar.startswith("hi"):<o:p></o:p></p>
<p class="MsoNormal"> raise ValueError("bar should never say hi")<o:p></o:p></p>
<p class="MsoNormal"> return True<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> if foo(["a","b","c"]):<o:p></o:p></p>
<p class="MsoNormal"> print("Ok")<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> TypeError: 'type' object is not subscriptable<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The problem is that python doesn't recognize list[str] as a type. Pycharm handles it, and everything works fine if I'm using a non-subscripted type, like plain old int, or str, or anything else.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is this a bug, or is it something python simply hasn't implemented yet, or is it something that's not going to be implemented?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there a workaround?<o:p></o:p></p>
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