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Does Haskell require a garbage collector?
... the user types "clear"; so the lifetime of this must be determined dynamically, and this is why dynamic memory management is necessary.
So in this sense, automated dynamic memory allocation is necessary, and in practice this means: yes, Haskell requires a garbage collector, since garbage collectio...
Drop multiple tables in one shot in mysql
...e A has two children B and C. Then we can use the following syntax to drop all tables.
DROP TABLE IF EXISTS B,C,A;
This can be placed in the beginning of the script instead of individually dropping each table.
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Declaring variables inside loops, good practice or bad practice?
...their scope is restricted to inside the loop. It cannot be referenced nor called outside of the loop.
This way:
If the name of the variable is a bit "generic" (like "i"), there is no risk to mix it with another variable of same name somewhere later in your code (can also be mitigated using the -W...
Data Modeling with Kafka? Topics and Partitions
...
When structuring your data for Kafka it really depends on how it´s meant to be consumed.
In my mind, a topic is a grouping of messages of a similar type that will be consumed by the same type of consumer so in the example above, I would just have a single topic and...
What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
SQL SELECT speed int vs varchar
...ent date types:
int fields occupy between 2 and 8 bytes, with 4 being usually more than enough ( -2147483648 to +2147483647 )
character types occupy 4 bytes plus the actual strings.
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Traits in PHP – any real world examples/best practices? [closed]
...
My personal opinion is that there is actually very little application for traits when writing clean code.
Instead of using traits to hack code into a class it is better to pass in the dependencies via the constructor or via setters:
class ClassName {
protected...
Swift Beta performance: sorting arrays
...t))
// [-1, 0, 2, 2, 5, 8, 1234]
// [-1, 0, 2, 2, 5, 8, 1234]
Both are called in the same program as written.
var x_swift = CInt[](count: n, repeatedValue: 0)
var x_c = CInt[](count: n, repeatedValue: 0)
for var i = 0; i < n; ++i {
x_swift[i] = CInt(random())
x_c[i] = CInt(random())
}...
Is there a printf converter to print in binary format?
..._PATTERN"\n",
BYTE_TO_BINARY(m>>8), BYTE_TO_BINARY(m));
You need all the extra quotes unfortunately. This approach has the efficiency risks of macros (don't pass a function as the argument to BYTE_TO_BINARY) but avoids the memory issues and multiple invocations of strcat in some of the oth...
Is there a method to generate a UUID with go language
...ic range. rand.Read returns random bytes in the range 0-255, which are not all valid values for a UUID. As far as I can tell, this should be done for all the values in the slice though.
If you are on linux, you can alternatively call /usr/bin/uuidgen.
package main
import (
"fmt"
"log"
...