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Table with fixed header and fixed column on pure css
...-index: 2;
}
/* Just to display it nicely: */
thead th {
background: #000;
color: #FFF;
/* Ensure this stays above the emulated border right in tbody th {}: */
z-index: 1;
}
tbody th {
background: #FFF;
border-right: 1px solid #CCC;
/* Browsers tend to drop borders on sticky elemen...
Optional Parameters with C++ Macros
...S(message, size) PrintString(message, size, 0)
#define PRINT_STRING_3_ARGS(message, size, style) PrintString(message, size, style)
#define GET_4TH_ARG(arg1, arg2, arg3, arg4, ...) arg4
#define PRINT_STRING_MACRO_CHOOSER(...) \
GET_4TH_ARG(__VA_ARGS__, PRINT_STRING_3_ARGS, \
...
C++ preprocessor __VA_ARGS__ number of arguments
....) \
PP_ARG_N(__VA_ARGS__)
#define PP_ARG_N( \
_1, _2, _3, _4, _5, _6, _7, _8, _9,_10, \
_11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
_21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
_31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \
_41,_42,_43,_44,_45,_46,_47...
Why is the order in dictionaries and sets arbitrary?
... was written before the implementation of the dict type changed, in Python 3.6. Most of the implementation details in this answer still apply, but the listing order of keys in dictionaries is no longer determined by hash values. The set implementation remains unchanged.
The order is not arbitrary,...
Should I implement __ne__ in terms of __eq__ in Python?
...
Daniel DiPaoloDaniel DiPaolo
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...
Elegant ways to support equivalence (“equality”) in Python classes
...
342
Consider this simple problem:
class Number:
def __init__(self, number):
self.num...
Python __str__ versus __unicode__
... method:
def __str__(self):
return unicode(self).encode('utf-8')
In 3.0, str contains characters, so the same methods are named __bytes__() and __str__(). These behave as expected.
share
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im...
When is “i += x” different from “i = i + x” in Python?
...
3 Answers
3
Active
...
Get fully qualified class name of an object in Python
...as, the module name is explicitly excluded from __qualname__
# in Python 3.
module = o.__class__.__module__
if module is None or module == str.__class__.__module__:
return o.__class__.__name__ # Avoid reporting __builtin__
else:
return module + '.' + o.__class__.__name__
bar = foo...
What is the most efficient/elegant way to parse a flat table into a tree?
...id, descendant_id) VALUES
(1,1), (1,2), (1,4), (1,6),
(2,2), (2,4),
(3,3), (3,5),
(4,4),
(5,5),
(6,6);
Now you can get a tree starting at node 1 like this:
SELECT f.*
FROM FlatTable f
JOIN ClosureTable a ON (f.id = a.descendant_id)
WHERE a.ancestor_id = 1;
The output (in MySQL c...