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How does comparison operator works with null int?
..."Operators" section:
When you perform comparisons with nullable types, if the value of one of the nullable types is null and the other is not, all comparisons evaluate to false except for !=
So both a > b and a < b evaluate to false since a is null...
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PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
... being necessary anyway in the long run.
Native prepares doesn't make any difference for security. The pseudo-prepared statements will still escape query parameter values, it will just be done in the PDO library with strings instead of on the MySQL server using the binary protocol. In other words, t...
Base64 length calculation?
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Consider if you have one byte of input. That will produce four characters of output. But only two output characters are needed to encode the input. So two characters will be padding.
– David Schwartz
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Insert line after first match using sed
... about inserting a choice line of text after the first line matching a specific string using the sed command. I have ...
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How to return smart pointers (shared_ptr), by reference or by value?
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Return smart pointers by value.
As you've said, if you return it by reference, you won't properly increment the reference count, which opens up the risk of deleting something at the improper time. That alone should be enough reason to not return by reference. Interfaces sh...
Add object to ArrayList at specified index
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After you add object2 to position 2, it will move object3 to position 3.
If you want object3 to be at position3 all the time I'd suggest you use a HashMap with position as key and object as a value.
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How can I see the assembly code for a C++ program?
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Ask the compiler
If you are building the program yourself, you can ask your compiler to emit assembly source. For most UNIX compilers use the -S switch.
If you are using the GNU assembler, compiling with -g -Wa,-alh will give intermixed sou...
RegEx to exclude a specific string constant [duplicate]
Can regular expression be utilized to match any string except a specific string constant let us say "ABC" ? Is this possible to exclude just one specific string constant? Thanks your help in advance.
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Understanding Linux /proc/id/maps
... - This describes how pages in the region can be accessed. There are four different permissions: read, write, execute, and shared. If read/write/execute are disabled, a - will appear instead of the r/w/x. If a region is not shared, it is private, so a p will appear instead of an s. If the process at...
How do I change bash history completion to complete what's already on the line?
...h-backward
"\e[B": history-search-forward
or equivalently,
# ~/.bashrc
if [[ $- == *i* ]]
then
bind '"\e[A": history-search-backward'
bind '"\e[B": history-search-forward'
fi
(the if statement checks for interactive mode)
Normally, Up and Down are bound to the Readline functions previ...