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python [2026/07/30 04:48] – carlpython [2026/09/09 19:44] (current) – carl
Line 67: Line 67:
  
 Python does not have a compacting garbage collector, so memory allocations eventually fill up RSS.   When a mixture of long lived and short lived objects are allocated around the same time, Python (pymalloc) allocates them possibly in the same arena.  When the short lived object is free, the long lived object holds the arena alive for ever. Python does not have a compacting garbage collector, so memory allocations eventually fill up RSS.   When a mixture of long lived and short lived objects are allocated around the same time, Python (pymalloc) allocates them possibly in the same arena.  When the short lived object is free, the long lived object holds the arena alive for ever.
 +
 +
 +==== Misc. APIs ====
 +List and Tuple types have an ''index'' method, but it throws if the element isn't present.   This forces you to use Exceptions as flow control.
 +
 +''set()'' objects don't support the ''del'' keyword:
 +
 +    >>> s = set()
 +    >>> s.add(99)
 +    >>> del s[99]
 +    Traceback (most recent call last):
 +      File "<stdin>", line 1, in <module>
 +    TypeError: 'set' object doesn't support item deletion
 +
 +
 +''enumerate(iterable, start=0)''
 +
 +The ''start'' parameter doesn't do what I expect.   I would have expected it to start at the element listed, but instead it just adds start to the returned tuple index:
 +
 +    >>> for i, k in  enumerate([9, 8, 7], 1): print (i, k)
 +    ... 
 +    1 9
 +    2 8
 +    3 7
 +
 +I would have expected this to return 2 total elements instead:
 +
 +    ...
 +    1 8
 +    2 7
 + 
 +
 +
python.1785386926.txt.gz · Last modified: by carl