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Why use Abstract Base Classes in Python?
...sinstance(c, MyABC): # will be true
c.abc_method() # raises AttributeError
Unfortunately this one of those "just don't do that" traps (of which Python has relatively few!): avoid defining ABCs with both a __subclasshook__ and non-abstract methods. Moreover, you should make your definition of...
Get line number while using grep
...l options
– Miro A.
Jul 9 '10 at 16:05
56
You don't need -r if you specify multiple files. You on...
Where can I set environment variables that crontab will use?
... does not allow environment variables to be declared and will throw syntax errors in the cron.log. Workaround can be done per-entry:
# m h dom mon dow command
* * * * * export LC_ALL=nb_NO.UTF-8; sleep 5s && echo "yo"
...
CMake: Print out all accessible variables in a script
...
Using the get_cmake_property function, the following loop will print out all CMake variables defined and their values:
get_cmake_property(_variableNames VARIABLES)
list (SORT _variableNames)
foreach (_variableName ${_variableNames})
...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 1
...luding using string.encode('utf-8') and unicode(string) , but I get the error:
16 Answers
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Java String remove all non numeric characters
Trying to remove all letters and characters that are not 0-9 and a period. I'm using Character.isDigit() but it also removes decimal, how can I also keep the decimal?
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What techniques can be used to speed up C++ compilation times?
...is over. On some compilers, such as GCC, this might ICE (Internal Compiler Error) your compiler for lack of memory. So don't use this technique unless you know all the pros and cons.
Precompiled headers
Precompiled headers (PCHs) can save you a lot of time in compilation by compiling your header fil...
Changing iframe src with Javascript
I am trying to change an <iframe src=... > when someone clicks a radio button. For some reason my code is not working correctly and I am having trouble figuring out why. Here is what I have:
...
How to set or change the default Java (JDK) version on OS X?
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I get this error when sourcing: /Users/me/.zshrc:8: permission denied: /Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home
– cosbor11
Apr 4 '19 at 22:28
...
Select rows which are not present in other table
I've got two postgresql tables:
4 Answers
4
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