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Does C have a “foreach” loop construct?
...#include <string.h>
#include <stdbool.h>
#define FOREACH_COMP(INDEX, ARRAY, ARRAY_TYPE, SIZE) \
__extension__ \
({ \
bool ret = 0; \
if (__builtin_types_compatible_p (const char*, ARRAY_TYPE)) \
ret = INDEX < strlen ((const char*)ARRAY); \
else \
ret = IND...
How to create cron job using PHP?
...syntax of scheduling a new job may seem daunting at first glance, it's actually relatively simple to understand once you break it down. A cron job will always have five columns each of which represent a chronological 'operator' followed by the full path and command to execute:
* * * * * home/path/t...
How to concatenate strings in twig
...like Alessandro said, and here it is in the documentation:
~: Converts all operands into strings and concatenates them. {{ "Hello
" ~ name ~ "!" }} would return (assuming name is 'John') Hello John!. – http://twig.sensiolabs.org/doc/templates.html#other-operators
And here is an example so...
How do you access the matched groups in a JavaScript regular expression?
...le (match != null) {
// matched text: match[0]
// match start: match.index
// capturing group n: match[n]
console.log(match[0])
match = myRegexp.exec(myString);
}
Edit: 2019-09-10
As you can see the way to iterate over multiple matches was not very intuitive. This lead to the...
Best way to test if a row exists in a MySQL table
...on in the comments, that in this situation:
SELECT 1 FROM my_table WHERE *indexed_condition* LIMIT 1
Is superior to:
SELECT * FROM my_table WHERE *indexed_condition* LIMIT 1
This is because the first query can be satisfied by the index, whereas the second requires a row look up (unless possibl...
Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
...
To answer this question, we have to look at how indexing a multidimensional array works in Numpy. Let's first say you have the array x from your question. The buffer assigned to x will contain 16 ascending integers from 0 to 15. If you access one element, say x[i,j], Nu...
Convert JavaScript string in dot notation into an object reference
...n elegant one-liner that's 10x shorter than the other solutions:
function index(obj,i) {return obj[i]}
'a.b.etc'.split('.').reduce(index, obj)
[edit] Or in ECMAScript 6:
'a.b.etc'.split('.').reduce((o,i)=>o[i], obj)
(Not that I think eval always bad like others suggest it is (though it usua...
How do I prevent site scraping? [closed]
...ce
Search engines may not run JavaScript either, thus preventing them from indexing your content. This may not be a problem for search results pages, but may be for other things, such as article pages.
Obfuscate your markup, network requests from scripts, and everything else.
If you use Ajax and ...
html5 localStorage error with Safari: “QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to
...wsing mode, it appears as though localStorage is available, but trying to call setItem throws an exception.
store.js line 73
"QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to add something to storage that exceeded the quota."
What happens is that the window object still exposes localS...
Comparing two dataframes and getting the differences
...dentical rows and columns. In fact, all dataframes axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order.
If I got you right, you want not to find changes, but symmetric difference. For that, one approach might be concatenate datafr...