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How do I check if a string is valid JSON in Python?
...on script returns a boolean if a string is valid json:
import json
def is_json(myjson):
try:
json_object = json.loads(myjson)
except ValueError as e:
return False
return True
Which prints:
print is_json("{}") #prints True
print is_json("{asdf}") ...
XPath contains(text(),'some string') doesn't work when used with node with more than one Text subnod
...ng the string-value of the node in the node-set that is first in document order. Hence, it can match only the first text node in your <Comment> element -- namely BLAH BLAH BLAH. Since that doesn't match, you don't get a <Comment> in your results.
You need to change this to
//*[text(...
Objective-C Static Class Level variables
...ing a Class Object in Apple's Objective-C docs.
– big_m
Oct 3 '11 at 16:02
...
Const before or const after?
...
The order of the keywords in a declaration isn't all that fixed. There are many alternatives to "the one true order". Like this
int long const long unsigned volatile i = 0;
or should it be
volatile unsigned long long int con...
Lock, mutex, semaphore… what's the difference?
...task to another. A mutex is meant to be taken and released, always in that order, by each task that uses the shared resource it protects. By contrast, tasks that use semaphores either signal or wait—not both."
– ToolmakerSteve
Feb 2 '17 at 5:14
...
Why does 'continue' behave like 'break' in a Foreach-Object?
..., it simulates the continue in a loop.
1..100 | ForEach-Object {
if ($_ % 7 -ne 0 ) { return }
Write-Host "$($_) is a multiple of 7"
}
There is a gotcha to be kept in mind when refactoring. Sometimes one wants to convert a foreach statement block into a pipeline with a ForEach-Object cmdl...
Disable individual Python unit tests temporarily
...he unittest.skip decorator.
@unittest.skip("reason for skipping")
def test_foo():
print('This is foo test case.')
@unittest.skip # no reason needed
def test_bar():
print('This is bar test case.')
For other options, see the docs for Skipping tests and expected failures.
...
How do you round to 1 decimal place in Javascript?
...)
You might want to create a function for this:
function roundedToFixed(_float, _digits){
var rounded = Math.pow(10, _digits);
return (Math.round(_float * rounded) / rounded).toFixed(_digits);
}
share
|
...
How to output only captured groups with sed?
... groups and their back references. The back references are numbered in the order the groups appear, but they can be used in any order and can be repeated:
echo "foobarbaz" | sed -r 's/^foo(.*)b(.)z$/\2 \1 \2/'
outputs "a bar a".
If you have GNU grep (it may also work in BSD, including OS X):
ec...
How to detect if a function is called as constructor?
... // except in in EcmaScript 5 strict mode.
&& !this.__previouslyConstructedByX) {
isConstructor = true;
this.__previouslyConstructedByX = true;
}
alert(isConstructor);
}
Obviously this is not ideal, since you now have an extra useless property on ever...