Python Style Question

Martin Kemp martin.kemp at ingg.com
Wed Oct 29 12:25:57 CET 2014


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On 29/10/2014 10:45, Anton wrote:
> Let's say I have an incoming list of values *l*. Every element of
> *l* can be one of the following options: 1) an integer value 2) a
> string in form of '<int_value>', e.g. '7' 3) a string with a json
> serialization of an integer value, e.g. '"7"' 4) something else
> that should be ignored
> 
> I need to transform this list into another list with values from
> options 1)-3) coerced to int. The code below should do this.
> 
> 
> Variant 1 ===
> 
> values = [] for c in l: # Case 1) or 2) try: c_int = int(c) except
> ValueError: pass else: values.add(c_int) continue
> 
> # Case 3) try: c_int = int(json.loads(c)) except ValueError: pass 
> else: values.add(c_int) continue
> 
> ===
> 
> Is this code ugly? Does it follow EAFP? Am I missing something in
> language best practice?
> 
> Or maybe below is more preferable way with a nested try...except
> clause?
> 
> Variant 2 === values = [] for c in l: # Case 1) or 2) try: c_int =
> int(c) except ValueError:  # Case 3) try: c_int =
> int(json.loads(c)) except ValueError: pass else: values.add(c_int) 
> continue  else: values.add(c_int) continue ===
> 
> Thanks, Anton.
> 
> 

Your first example is perfectly fine and is EAFP

Personally, I prefer to avoid nesting when it's not necessary.

- -- 
Martin Kemp (martin.kemp at ingg.com)
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