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Is sizeof(bool) defined in the C++ language standard?
...r, since 0xbadf00d asked about the standard, not some specific/arbitrarily selected compiler implementation, right?
– Christopher Creutzig
Dec 12 '13 at 22:27
13
...
Convert data.frame column format from character to factor
...yr::mutate_if() to convert all character columns or dplyr::mutate_at() for select named character columns to factors:
library(dplyr)
# all character columns to factor:
df <- mutate_if(df, is.character, as.factor)
# select character columns 'char1', 'char2', etc. to factor:
df <- mutate_at(d...
Use tab to indent in textarea
...which;
if (keyCode == 9) {
e.preventDefault();
var start = this.selectionStart;
var end = this.selectionEnd;
// set textarea value to: text before caret + tab + text after caret
$(this).val($(this).val().substring(0, start)
+ "\t"
+ $(this).val...
Determine version of Entity Framework I am using?
...";
var assemblies = System.AppDomain.CurrentDomain.GetAssemblies().Select(x => x.FullName).ToList();
foreach(var asm in assemblies)
{
var fragments = asm.Split(new char[] { ',', '{', '}' }, StringSplitOptions.RemoveEmptyEntries).Select(x=> x.Trim()).ToList()...
CentOS+Nginx+PHP+MySQL详细配置(图解) - PHP - 清泛IT论坛，有思想、有深度
...PHP-FPM说白了是一个管理FastCGI的一个管理器，它作为PHP的插件纯在，在安装PHP要想使用PHP-FPM时就需要把PHP-FPM以补丁的形式安装到PHP中，而且PHP要与PHP-FPM版本一致，这是必须的，切记！
首先我们把PHP和PHP-FPM...
String.Join method that ignores empty strings?
... simpler, since you can do it in SQL directly:
PostgreSQL & MySQL:
SELECT
concat_ws(' / '
, NULLIF(searchTerm1, '')
, NULLIF(searchTerm2, '')
, NULLIF(searchTerm3, '')
, NULLIF(searchTerm4, '')
) AS RPT_SearchTerms;
And even with the glorious MS-SQ...
How do I print to the debug output window in a Win32 app?
...tput is shown in the Output window. To actually see the output you have to select Debug from the Show output from dropdown. If you for some reason are running your process outside a debugger you can use DebugView to see debug output from all processes.
– Martin Liversage
...
How does database indexing work? [closed]
...arising from the file systems size limits, careful thought must be used to select the correct fields to index.
Since indices are only used to speed up the searching for a matching field within the records, it stands to reason that indexing fields used only for output would be simply a waste of disk...
How do I match any character across multiple lines in a regular expression?
...o_mod_m (source).
As for oracle (it is POSIX based), use n option (demo): select regexp_substr('abcde' || chr(10) ||' fghij<Foobar>', '(.*)<Foobar>', 1, 1, 'n', 1) as results from dual
POSIX-based engines:
A mere . already matches line breaks, no need to use any modifiers, see bas...
How can I delete the current line in Emacs?
...lest way to delete (kill) a full line, from any point
on the line, without selecting anything, is:
C-w ; kill-region
It is versatile in deleting whatever is selected, or a line by default
if nothing is selected.
Given the question, you're probably also interested in replicating
Vim's "yank", yy...