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How should one use std::optional?
I'm reading the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When...
Where in memory are my variables stored in C?
...sidering that the memory is divided into four segments: data, heap, stack, and code, where do global variables, static variables, constant data types, local variables (defined and declared in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and calloc...
SQL: IF clause within WHERE clause
...ion in most cases. In my case, I wanted the change the comparison operator and hence I used the next approach.
– Birla
Nov 15 '14 at 11:59
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How does “do something OR DIE()” work in PHP?
I'm writing a php app to access a MySQL database, and on a tutorial, it says something of the form
4 Answers
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What is better, adjacency lists or adjacency matrices for graph problems in C++?
...ts or adjacency matrix, for graph problems in C++?
What are the advantages and disadvantages of each?
11 Answers
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Return multiple values in JavaScript?
... first: getFirstValue(),
second: getSecondValue(),
};
}
And to access them:
var values = getValues();
var first = values.first;
var second = values.second;
Or with ES6 syntax:
const {first, second} = getValues();
* See this table for browser compatibility. Basically, all mod...
What is the meaning of prepended double colon “::”?
...wered Nov 24 '10 at 16:27
Wyatt AndersonWyatt Anderson
8,42811 gold badge1919 silver badges2424 bronze badges
...
What is the JSF resource library for and how should it be used?
The JSF <h:outputStylesheet> , <h:outputScript> and <h:graphicImage> components have a library attribute. What is this and how should this be used? There are a lot of examples on the web which use it as follows with the common content/file type css , js and img (or ima...
Cookies vs. sessions
...r the sake of creating a login system for my website, I read about cookies and sessions and their differences (cookies are stored in the user's browser and sessions on the server). At that time, I preferred cookies (and who does not like cookies?!) and just said: "who cares? I don't have any good de...
Ignoring time zones altogether in Rails and PostgreSQL
I'm dealing with dates and times in Rails and Postgres and running into this issue:
2 Answers
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