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PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
... the new value.
So loop 1, the value and $arr[2] become $arr[0], which is 'foo'.
Loop 2, the value and $arr[2] become $arr[1], which is 'bar'.
Loop 3, the value and $arr[2] become $arr[2], which is 'bar' (because of loop 2).
The value 'baz' is actually lost at the first call of the second foreach lo...
Using querySelectorAll to retrieve direct children
...
let myDiv = getElementById("myDiv");
myDiv.querySelectorAll(":scope > .foo");
Note that in some cases you can also skip .querySelectorAll and use other good old-fashioned DOM API features. For example, instead of myDiv.querySelectorAll(":scope > *") you could just write myDiv.children, for...
How to implement Enums in Ruby?
...
Two ways. Symbols (:foo notation) or constants (FOO notation).
Symbols are appropriate when you want to enhance readability without littering code with literal strings.
postal_code[:minnesota] = "MN"
postal_code[:new_york] = "NY"
Constants a...
Merge, update, and pull Git branches without using checkouts
...sourceBranch>:<destinationBranch>
Examples:
# Merge local branch foo into local branch master,
# without having to checkout master first.
# Here `.` means to use the local repository as the "remote":
git fetch . foo:master
# Merge remote branch origin/foo into local branch foo,
# without ...
Forced naming of parameters in Python
...meters and
may only be passed used keyword arguments.
>>> def foo(pos, *, forcenamed):
... print(pos, forcenamed)
...
>>> foo(pos=10, forcenamed=20)
10 20
>>> foo(10, forcenamed=20)
10 20
>>> foo(10, 20)
Traceback (most recent call last):
File "<stdin&...
How to tell bash that the line continues on the next line
...ng, and the backslash can be omitted. Some examples:
# In general
$ echo "foo" \
> "bar"
foo bar
# Pipes
$ echo foo |
> cat
foo
# && and ||
$ echo foo &&
> echo bar
foo
bar
$ false ||
> echo bar
bar
Different, but related, is the implicit continuation inside quotes. ...
How to make a cross-module variable?
...des __builtin__ -- which is all of them, by default.
a.py contains
print foo
b.py contains
import __builtin__
__builtin__.foo = 1
import a
The result is that "1" is printed.
Edit: The __builtin__ module is available as the local symbol __builtins__ -- that's the reason for the discrepancy be...
postgresql return 0 if returned value is null
...verride this you can use coalesce (as suggested by Luc M).
$ create table foo (bar int);
CREATE TABLE
$ select avg(bar) from foo;
avg
-----
(1 row)
$ select coalesce(avg(bar), 0) from foo;
coalesce
----------
0
(1 row)
$ insert into foo values (3);
INSERT 0 1
$ insert into foo value...
How to get rid of `deprecated conversion from string constant to ‘char*’` warnings in GCC?
...ar problem, I solved it like this:
#include <string.h>
extern void foo(char* m);
int main() {
// warning: deprecated conversion from string constant to ‘char*’
//foo("Hello");
// no more warning
char msg[] = "Hello";
foo(msg);
}
Is this an appropriate way of solvi...
What is the “->” PHP operator called and how do you say it when reading code out loud? [closed]
...
I call it "dart"; as in $Foo->bar() : "Foo dart bar"
Since many languages use "dot" as in Foo.bar(); I wanted a one-syllable word to use. "Arrow" is just too long-winded! ;)
Since PHP uses . "dot" for concatenation (why?) I can't safely say "dot...