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Why isn't vector a STL container?
... &x = b[5]; // that's what really happens
bool y = b[5]; // implicitly converted to bool
assert(b[5] == false); // converted to bool
assert(b[6] == b[7]); // bool operator==(const reference &, const reference &);
b[5] = true; // assignment on reference
assert(b[5] == true); // and actua...
Django Rest Framework File Upload
... very helpful thank you a lot. But i don't understand, why you are converting dict data to QueryDict in parser? In my case in Django, normal dictionary data work perfectly without converting.
– Metehan Gülaç
Apr 12 at 20:15
...
Python pandas Filtering out nan from a data selection of a column of strings
... },
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
});
}
});
...
What does $_ mean in PowerShell?
...dItem | Add-Member -Type NoteProperty -Name Bar -Value $_.Name -PassThru | Select Bar ... Well, it can work if you have a $_ in the scope where you're executing that pipeline. But that's very different from what you usually mean when trying to write something like that.
– Joey
...
What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...
TEXT and CHAR will convert to/from the character set they have associated with time. BLOB and BINARY simply store bytes.
BLOB is used for storing binary data while Text is used to store large string.
BLOB values are treated as binary strings ...
What is the difference between a pseudo-class and a pseudo-element in CSS?
...
The CSS 3 selector recommendation is pretty clear about both, but I'll try to show the differences anyway.
Pseudo-classes
Official description
The pseudo-class concept is introduced to permit selection based on information that l...
How can I cast int to enum?
...urEnum is dynamic and will only be known at runtime, and what I want is to convert to Enum?
– Shimmy Weitzhandler
Feb 19 '12 at 9:56
235
...
Media Queries: How to target desktop, tablet, and mobile?
...1281px) { /* hi-res laptops and desktops */ }
In practice, many designers convert pixels to ems, largely because ems afford better zooming. At standard zoom 1em === 16px, multiply pixels by 1em/16px to get ems. For example, 320px === 20em.
In response to the comment, min-width is standard in "mobil...
What is the difference between bindParam and bindValue?
...iated parameter markers
Example:
$value = 'foo';
$s = $dbh->prepare('SELECT name FROM bar WHERE baz = :baz');
$s->bindParam(':baz', $value); // use bindParam to bind the variable
$value = 'foobarbaz';
$s->execute(); // executed with WHERE baz = 'foobarbaz'
or
$value = 'foo';
$s = $dbh...