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Difference between object and class in Scala
....type = Commerce$@6eb2756 scala> classOf[Commerce] <console>:23: error: not found: type Commerce classOf[Commerce] ^ scala> new Commerce <console>:23: error: not found: type Commerce new Commerce ^
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Difference between const & const volatile
...rked as const volatile will not be permitted to be changed by the code (an error will be raised due to the const qualifier) - at least through that particular name/pointer.
The volatile part of the qualifier means that the compiler cannot optimize or reorder access to the object.
In an embedded sy...
How to detect Adblock on my website?
...your layout gets distorted or ad loads slowly, user can catch a glimpse of error that doesn't relate to him. Also be aware that Adblock is taking measures to block obtrusive messages targeted at ABP users. If you want to ask user for unblocking, do it through simple hideable message that sits outsi...
is not JSON serializable
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Now getting error --> 'NoneType' object has no attribute 'concrete_model' ... And using Django 1.4+
– tuna
May 28 '13 at 11:42
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How can I make pandas dataframe column headers all lowercase?
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df.columns = df.columns.str.lower()
is the easiest but will give an error if some headers are numeric
if you have numeric headers then use this:
df.columns = [str(x).lower() for x in df.columns]
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Why are Oracle table/column/index names limited to 30 characters?
...RRM which is limited to 255 characters, and which most clients use to make errors visible. I suspect increasing the allowable size of constraint names significantly would impact the ability to report on the violations (especially where a constraint violation has been bubbled up through a few layers ...
Explain the encapsulated anonymous function syntax
...// true? false? why?
The above code should actually produce a SyntaxError, since a Block can only contain statements (and the ECMAScript Specification doesn't define any function statement), but most implementations are tolerant, and will simply take the second function, the one which alerts ...
Python syntax for “if a or b or c but not all of them”
...'x', 'y', 'z'])
args = parser.parse_args()
if len(args.abc) != 3:
parser.error('expected 3 arguments')
print(args.abc)
Here are some usage examples:
# default case
wim@wim-zenbook:/tmp$ ./three_or_none.py
['x', 'y', 'z']
# explicit case
wim@wim-zenbook:/tmp$ ./three_or_none.py 1 2 3
['1', '2'...
How to use SSH to run a local shell script on a remote machine?
...;'END2'
# Another bunch of commands on another host
wall <<'ENDWALL'
Error: Out of cheese
ENDWALL
ftp ftp.secureftp-test.com <<'ENDFTP'
test
test
ls
ENDFTP
END2
ENDSSH
You can actually have a conversation with some services like telnet, ftp, etc. But remember that heredoc just sends th...
git push says “everything up-to-date” even though I have local changes
...t I am wanting to add a new project to a github I sometimes forget and the error message leads me to think I did something really wrong - then of course DUH! commit Only happens to me when I am created new backup repositories and I forget
– Tom Stickel
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