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Error in if/while (condition) {: missing Value where TRUE/FALSE needed
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I ran into this when checking on a null or empty string
if (x == NULL || x == '') {
changed it to
if (is.null(x) || x == '') {
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Creating Scheduled Tasks
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using Microsoft.Win32.TaskScheduler;
class Program
{
static void Main(string[] args)
{
// Get the service on the local machine
using (TaskService ts = new TaskService())
{
// Create a new task definition and assign properties
TaskDefinition td = ts.NewTask...
Is there a Sleep/Pause/Wait function in JavaScript? [duplicate]
..., the concern isn't around anonymous functions, it's with code passed as a string, which must be executed via eval.
– Michael Haren
May 22 '18 at 11:12
add a comment
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how get yesterday and tomorrow datetime in c#
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The trick is to use "DateTime" to manipulate dates; only use integers and strings when you need a "final result" from the date.
For example (pseudo code):
Get "DateTime tomorrow = Now + 1"
Determine date, day of week, day of month - whatever you want - of the resulting date.
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Format number as fixed width, with leading zeros [duplicate]
...to use sprintf. This uses C style formatting codes embedded in a character string to indicate the format of any other arguments passed to it. For example, the formatting code %3d means format a number as integer of width 3:
a <- seq(1,101,25)
sprintf("name_%03d", a)
[1] "name_001" "name_026" "n...
Correct way to check if a type is Nullable [duplicate]
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@ELMOJO Why would you expect that? String isn't a nullable value type.
– Jon Skeet
Sep 11 '18 at 22:09
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CSS values using HTML5 data attribute [duplicate]
...rding to caniuse.com, the function is still widely unsupported (except for strings in the content attribute of pseudo-elements). caniuse.com/#feat=css3-attr
– ne1410s
Nov 25 '16 at 8:58
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When and why should I use a namedtuple instead of a dictionary? [duplicate]
...don't have keys, so hashability isn't an issue.
However, they have a more stringent restriction -- their key-equivalents, "field names", have to be strings.
Basically, if you were going to create a bunch of instances of a class like:
class Container:
def __init__(self, name, date, foo, bar):
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How to check if a JavaScript variable is NOT undefined? [duplicate]
...could take which would also match that condition - e.g. 0, null, '' (empty string). These are called "falsy" values.
– Allan Jardine
Nov 9 '18 at 16:25
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Double negation (!!) in javascript - what is the purpose? [duplicate]
...alent to false in conditional statements:
false
null
undefined
The empty string "" (\ '')
The number 0
The number NaN
All other values are equivalent to true.
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