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How can I check if a var is a string in JavaScript?
...
You were close:
if (typeof a_string === 'string') {
// this is a string
}
On a related note: the above check won't work if a string is created with new String('hello') as the type will be Object instead. There are complicated solutions to work a...
demystify Flask app.secret_key
If app.secret_key isn't set, Flask will not allow you to set or access the session dictionary.
2 Answers
...
How to create a MySQL hierarchical recursive query
...s, path IDs, or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inn...
Capitalize or change case of an NSString in Objective-C
...ingString:lowercase];
}
- (NSString *)realSentenceCapitalizedString {
__block NSMutableString *mutableSelf = [NSMutableString stringWithString:self];
[self enumerateSubstringsInRange:NSMakeRange(0, [self length])
options:NSStringEnumerationBySentences
...
Which websocket library to use with Node.js? [closed]
...process.env.PORT || 5000;
var app = express();
app.use(express.static(__dirname+ "/../"));
app.get('/someGetRequest', function(req, res, next) {
console.log('receiving get request');
});
app.post('/somePostRequest', function(req, res, next) {
console.log('receiving pos...
How to specify data attributes in razor, e.g., data-externalid=“23151” on @this.Html.CheckBoxFor(…)
...el.MyBoolProperty,
new {
@class = "myCheckBox",
data_externalid = "23521"
}
)
The _ will automatically be converted to - in the resulting markup:
<input type="checkbox" name="MyModel.MyBoolProperty" data-externalid="23521" class="myCheckBox" />
And that's true f...
Precision String Format Specifier In Swift
...
a simple way is:
import Foundation // required for String(format: _, _)
print(String(format: "hex string: %X", 123456))
print(String(format: "a float number: %.5f", 1.0321))
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Unable to install gem - Failed to build gem native extension - cannot load such file — mkmf (LoadErr
...ing so i had to run open /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg
That didnt work for me at first because the version of CommandLineTools i had installed did not have the "Packages" folder. So i uninstalled and reinstalled like this:
rm -rf /Library/Devel...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...re readable.
Using the sample data provided:
>>> %timeit df3.reset_index().drop_duplicates(subset='index', keep='first').set_index('index')
1000 loops, best of 3: 1.54 ms per loop
>>> %timeit df3.groupby(df3.index).first()
1000 loops, best of 3: 580 µs per loop
>>> %tim...
@try - catch block in Objective-C
...t length] - 1);
}
@finally {
NSLog(@"Finally condition");
}
Log:
[__NSCFConstantString characterAtIndex:]: Range or index out of bounds
Char at index 5 cannot be found
Max index is: 3
Finally condition
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