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Parse query string into an array
...alone is note accurate, it could display for example:
$url = "somepage?id=123&lang=gr&size=300";
parse_str() would return:
Array (
[somepage?id] => 123
[lang] => gr
[size] => 300
)
It would be better to combine parse_str() with parse_url() like so:
$url = "som...
Java: How to set Precision for double value? [duplicate]
...ts.
If you only want to print, use it this way:
System.out.printf("%.2f",123.234);
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Abandoning changes without deleting from history
...r you is to mark the old branch as "closed". If your old head is revision "123" then:
hg update -r 123
hg commit --close-branch -m 'Closing old branch'
hg update -C default
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What is the difference between char * const and const char *?
...you can't change the value they point at.
This:
int *const i3 = (int*) 0x12345678;
defines a const pointer to an integer and initializes it to point at memory location 12345678. You can change the int value at address 12345678, but you can't change the address that i3 points to.
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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...only match at that position or earlier. For example:
std::string test = "0123123";
size_t match1 = test.rfind("123"); // returns 4 (rightmost match)
size_t match2 = test.rfind("123", 2); // returns 1 (skipped over later match)
size_t match3 = test.rfind("123", 0); // returns std::string::npos (i...
Reshaping data.frame from wide to long format
... 1952 10,058
7: AFG Afghanistan 1953 23,557
8: ALB Albania 1953 11,123
9: AFG Afghanistan 1954 24,555
10: ALB Albania 1954 12,246
Some alternative notations:
melt(setDT(wide), id.vars = 1:2, variable.name = "year")
melt(setDT(wide), measure.vars = 3:7, variable.name = "year")
melt...
Assembly code vs Machine code vs Object code?
...
mov eax, 77
jmp anywhere
Machine code is pure hexadecimal code:
5F 3A E3 F1
I assume you mean object code as in an object file. This is a variant of machine code, with a difference that the jumps are sort of parameterized such that a linker can fill them in.
An assembler is used to convert a...
Why do x86-64 systems have only a 48 bit virtual address space?
...
lwn.net/SubscriberLink/655437/9a48cd3e7a8cbe8a <-- three years after this reply, we are already hitting these limits :) The HP Machine will have 320TB of memory and they can't provide it as a flat address space because of the 48-bit addressing limitation.
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How to create file execute mode permissions in Git on Windows?
...).
C:\Temp\TestRepo>git commit -m"Executable!"
[master (root-commit) 1f7a57a] Executable!
1 file changed, 0 insertions(+), 0 deletions(-)
create mode 100755 foo.sh
And now we have a single commit with a single executable file.
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A semantics for Bash scripts?
...ion.
$ foo() { echo $x; }
$ bar() { local x; echo $x; }
$ foo
$ bar
$ x=123
$ foo
123
$ bar
$ …
Environment and process "scope"
Subshells inherit the variables of their parent shells, but other kinds of processes don't inherit unexported names.
$ x=123
$ ( echo $x )
123
$ bash -c 'echo $x'...