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PHP check whether property exists in object or class
...ts( mixed $class , string $property )
if (property_exists($ob, 'a'))
isset( mixed $var [, mixed $... ] )
if (isset($ob->a))
isset() will return false if property is null
Example 1:
$ob->a = null
var_dump(isset($ob->a)); // false
Example 2:
class Foo
{
public $bar = null;...
Mercurial: Can I rename a branch?
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confirmed @Gili's comment with hg help branch: "--force set branch name even if it shadows an existing branch"
– Joshua Goldberg
Jun 30 '14 at 21:53
7
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How to hide elements without having them take space on the page?
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Try setting display:none to hide and set display:block to show.
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List the queries running on SQL Server
...spid int
, @stmt_start int
, @stmt_end int
, @sql_handle binary(20)
set @spid = XXX -- Fill this in
select top 1
@sql_handle = sql_handle
, @stmt_start = case stmt_start when 0 then 0 else stmt_start / 2 end
, @stmt_end = case stmt_end when -1 then -1 else stmt_end / 2 end
from s...
Match multiple cases classes in scala
...o have case A(x) | B(x) => println(x) be allowed where the type of x is set to the upper bound in the type system of whatever A(x) and B(x) produce.
– Mitch Blevins
Nov 10 '11 at 17:24
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In which situations do we need to write the __autoreleasing ownership qualifier under ARC?
...leasing * );
The compiler will then have to create a temporary variable, set at __autoreleasing. So:
NSError * error = nil;
[ database save: &error ];
Will be transformed to:
NSError * __strong error = nil;
NSError * __autoreleasing tmpError = error;
[ database save: &tmpError ];
error...
Removing pip's cache?
...hich can be used to configure pip to always ignore the cache -- pip config set global.cache-dir false configures pip to not use the cache "globally" (i.e. in all commands).
Since pip 20.1, pip has a pip cache command to manage the contents of pip's cache.
pip cache purge removes all the wheel files...
How to require a controller in an angularjs directive
...ne can communicate with the overall tabs to handle switching; an accordion set could ensure only one is open at a time; etc.
In either event, you have to use the two directives together for this to work. require is a way of communicating between components.
Check out the Guide page of directives f...
Changing Jenkins build number
...le) and update the build number in Jenkins to match it. I have tried to set the build number:
8 Answers
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Git says “Warning: Permanently added to the list of known hosts”
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Set LogLevel to ERROR (not QUIET) in ~/.ssh/config file to avoid seeing these errors:
Host *
StrictHostKeyChecking no
UserKnownHostsFile /dev/null
LogLevel ERROR
...