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Why isn't sizeof for a struct equal to the sum of sizeof of each member?
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Here's an example using typical settings for an x86 processor (all used 32 and 64 bit modes):
struct X
{
short s; /* 2 bytes */
/* 2 padding bytes */
int i; /* 4 bytes */
char c; /* 1 byte */
/* 3 padding bytes */
};
struct Y
{
int i; /* 4 bytes */...
How to get Enum Value from index in Java?
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230
Try this
Months.values()[index]
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npm install errors with Error: ENOENT, chmod
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136
Ok it looks like NPM is using your .gitignore as a base for the .npmignore file, and thus ignor...
How to select a single field for all documents in a MongoDB collection?
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answered Aug 31 '14 at 5:15
therealrootusertherealrootuser
6,08966 gold badges2323 silver badges4343 bronze badges
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How to loop through an associative array and get the key? [duplicate]
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340
You can do:
foreach ($arr as $key => $value) {
echo $key;
}
As described in PHP docs.
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Why does String.valueOf(null) throw a NullPointerException?
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203
The issue is that String.valueOf method is overloaded:
String.valueOf(Object)
String.valueOf(c...
Actual meaning of 'shell=True' in subprocess
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answered Jul 3 '10 at 18:46
Heath HunnicuttHeath Hunnicutt
16.3k22 gold badges3535 silver badges5858 bronze badges
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Adding additional data to select options using jQuery
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323
HTML Markup
<select id="select">
<option value="1" data-foo="dogs">this</opt...
Python “raise from” usage
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edited Jul 7 '19 at 23:56
answered Jul 15 '14 at 7:44
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R object identification
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data(cars)
obj <- lm(dist ~ speed, data=cars)
..etc.
If obj is an S3 or S4 object, you can also try methods or showMethods, showClass, etc. Patrick Burns' R Inferno has a pretty good section on this (sec #7).
EDIT: Dirk and Hadley mention str(obj) in their answers. It really is much bette...