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How to printf “unsigned long” in C?
...here it could print a minus sign when the format specifier was %lu. Technically it's undefined behavior but in reality the variable has an unpredictable value that gets passed to printf which printf then interprets as unsigned. I'm guessing bodacydo's original problem was flow reaching an incorrect ...
Mongoose populate after save
I cannot manually or automatically populate the creator field on a newly saved object ... the only way I can find is to re-query for the objects I already have which I would hate to do.
...
Proper Repository Pattern Design in PHP?
...te a complete example of a basic controller for viewing and editing Users.
All code must be fully testable and mockable.
The controller should have no idea where the data is stored (meaning it can be changed).
Example to show a SQL implementation (most common).
For maximum performance, controllers s...
How to count the number of set bits in a 32-bit integer?
...Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's ...
Makefile, header dependencies
...vided by the gnu preprocessor are a bit confusing. However, the removal of all directories from the build target with -MM is documented and not a bug [gpp]:
By default CPP takes the name of the main input file, deletes any
directory components and any file suffix such as ‘.c’, and appends ...
JPA CascadeType.ALL does not delete orphans
...eType.DELETE_ORPHAN, which can be used in conjunction with JPA CascadeType.ALL.
If you don't plan to use Hibernate, you'll have to explicitly first delete the child elements and then delete the main record to avoid any orphan records.
execution sequence
fetch main row to be deleted
fetch child...
Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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Using Build Flavors - Structuring source folders and build.gradle correctly
...
For the Java source:
src/main/java
src/flavor1/java
src/debug/java
are all 3 used to create a single output. This means they can't define the same class.
If you want to have a different version of the same class in the two flavor you'll need to create it in both flavors.
src/flavor1/java/com/f...
MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
...
Shortest distance between a point and a line segment
...ode, in C++. It presumes a class 2D-vector class vec2 {float x,y;}, essentially, with operators to add, subract, scale, etc, and a distance and dot product function (i.e. x1 x2 + y1 y2).
float minimum_distance(vec2 v, vec2 w, vec2 p) {
// Return minimum distance between line segment vw and point ...