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Python FAQ: How fast are exceptions? Is exception handling efficient in Python? (Python Tutorial: Using Try/Except Blocks for Error Handling)
By Guest on 9th November 2022 12:12:27 AM | Syntax: PYTHON | Views: 178


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  1. Is exception handling efficient in Python?
  2. How efficient is try except?
  3. Should you use exceptions in Python?
  4.  
  5.  
  6. How fast are exceptions?
  7. ========================
  8.  
  9. A try/except block is extremely efficient if no exceptions are raised.
  10. Actually catching an exception is expensive.  In versions of Python
  11. prior to 2.0 it was common to use this idiom:
  12.  
  13.    try:
  14.        value = mydict[key]
  15.    except KeyError:
  16.        mydict[key] = getvalue(key)
  17.        value = mydict[key]
  18.  
  19. This only made sense when you expected the dict to have the key almost
  20. all the time.  If that wasn't the case, you coded it like this:
  21.  
  22.   if key in mydict:
  23.       value = mydict[key]
  24.   else:
  25.       value = mydict[key] = getvalue(key)
  26.  
  27. For this specific case, you could also use "value =
  28. dict.setdefault(key, getvalue(key))", but only if the "getvalue()"
  29. call is cheap enough because it is evaluated in all cases.
  30.  
  31. Exception handling tips in Python ⚠ Write better Python code




  33.  
  34. Python Tutorial: Using Try/Except Blocks for Error Handling
  35. https://www.youtube.com/watch?v=NIWwJbo-9_8
  36.  
  37. [inline]
















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