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How to test equality of Swift enums with associated values
...{
case Name(String)
case Number(Int)
}
let t1 = SimpleToken.Number(123)
let t2 = SimpleToken.Number(123)
Before Swift 4.1
As others have noted, Swift doesn't synthesize the necessary equality operators automatically. Let me propose a cleaner (IMHO) implementation, though:
enum SimpleToke...
Restoring MySQL database from physical files
Is it possible to restore a MySQL database from the physical database files. I have a directory that has the following file types:
...
What is difference between monolithic and micro kernel?
... kernel can invoke functions directly. Examples of monolithic kernel based OSs: Unix, Linux.
In microkernels, the kernel is broken down into separate processes, known as servers. Some of the servers run in kernel space and some run in user-space. All servers are kept separate and run in different a...
Difference between malloc and calloc?
..., while malloc() leaves the memory uninitialized.
For large allocations, most calloc implementations under mainstream OSes will get known-zeroed pages from the OS (e.g. via POSIX mmap(MAP_ANONYMOUS) or Windows VirtualAlloc) so it doesn't need to write them in user-space. This is how normal malloc ...
Can a CSV file have a comment?
... I have more often seen and used: #Csv/Version 1.9 Time,ValueA,ValueB 0.0, 123, 456 0.1, 123, 349
– Crog
Aug 25 at 8:31
add a comment
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In Python script, how do I set PYTHONPATH?
...
It has been many years since this answer was posted, but I still want to add that if you want to make sure that Python checks the new directory before all of the others when importing, you should put the new directory first in the list, as in sys.path.insert(0, '/path/to...
Liquibase lock - reasons?
...he liquibase-scripts the lock was held.
<changeSet author="user" id="123">
<preConditions onFail="CONTINUE">
<not><sequenceExists sequenceName="SEQUENCE_NAME_SEQ" /></not>
</preConditions>
<createSequence sequenceName="SEQUENCE_NAME_SEQ"/&g...
Negation in Python
...herefore just replace your ! with not.
For your example, do this:
if not os.path.exists("/usr/share/sounds/blues") :
proc = subprocess.Popen(["mkdir", "/usr/share/sounds/blues"])
proc.wait()
For your specific example (as Neil said in the comments), you don't have to use the subprocess ...
Passing argument to alias in bash [duplicate]
...ed to use a function
$ foo () { /path/to/bar "$@" fixed args; }
$ foo abc 123
will be executed as if you had done
$ /path/to/bar abc 123 fixed args
To undefine an alias:
unalias foo
To undefine a function:
unset -f foo
To see the type and definition (for each defined alias, keyword, func...
How to check that a string is an int, but not a double, etc.?
... This will do some strange things such as return true for "+123". It is mitigated by that it's meant to return the true int but it still might not be what people want which is a strict int check.
– jgmjgm
Dec 11 '17 at 18:09
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