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How to output a multiline string in Bash?
How can I output a multipline string in Bash without using multiple echo calls like so:
7 Answers
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Create a pointer to two-dimensional array
...d T[10] are different types.
The following alternative doesn't work at all, because the element type of the array, when you view it as a one-dimensional array, is not uint8_t, but uint8_t[20]
uint8_t *matrix_ptr = l_matrix; // fail
The following is a good alternative
uint8_t (*matrix_ptr)[...
Instagram how to get my user id from username?
...ow:
https://www.instagram.com/{username}/?__a=1
E.g:
This url will get all information about a user whose username is therock
https://www.instagram.com/therock/?__a=1
Update i June-20-2019, the API is public now. No authentication required.
Update in December-11-2018, I needed to confirm t...
Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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SQL to determine minimum sequential days of access?
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@Artem: That was what I initially thought but when I thought about it, if you have an index on (UserId, CreationDate), the records will show up consecutively in the index and it should perform well.
– Mehrdad Afshari
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How to print a dictionary line by line in Python?
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Hmm. I think my problem is even worse than that. Basically I've parsed out some data from an HTML table, and I happened to store it in a dictionary, and now I'm trying to take that dictionary data and put it into a DataFrame before I export it all to an Oracle table....it's pret...
What is a proper naming convention for MySQL FKs?
...constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE T...
Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...type (and resolve to true and false) if the compiler supports it. (specifically, C++)
However, it would be better to check whether C++ is in use (via the __cplusplus macro) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note that removing the parentheses will bre...
How to turn on/off ReactJS 'development mode'?
...me helpers off during production. Just using the minified react will leave all those potential optimizations on the table as well.
Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV ...
Macro vs Function in C
...uct webpage page;
page.numButtons = 2;
num_button_holes(page) -> 8
Finally, macros can be difficult to debug, producing weird syntax errors or runtime errors that you have to expand to understand (e.g. with gcc -E), because debuggers cannot step through macros, as in this example:
#define prin...