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Check if key exists and iterate the JSON array using Python
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If all you want is to check if key exists or not
h = {'a': 1}
'b' in h # returns False
If you want to check if there is a value for key
h.get('b') # returns None
Return a default value if actual value is missing
h.get('b'...
Check if a value is an object in JavaScript
...o examine variable's properties, but it is not a bulletproof recipe (after all there's no recipe at all!) for checking whether it's an object, far from it. Since people tend to look for something to copy from here without doing any research, I'd highly recommend that they turn to the other, most upv...
How can I get the source code of a Python function?
...ole class: you can restore it method by method: dir(MyClass), then MyClass.__init__?? and so on.
– Valerij
May 8 '19 at 12:32
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The role of #ifdef and #ifndef
...o do something like that with the old #ifdef/#ifndef pair.
#if defined(ORA_PROC) || defined(__GNUC) && __GNUC_VERSION > 300
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Spring schemaLocation fails when there is no internet connection
...ks even though intellij doesn't recognize the classpath syntax inside schemalLocation and highlights it as a error.
– Upgradingdave
Feb 27 '13 at 19:33
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Conditional import of modules in Python
...ad of relying on the user; here's pySerial doing it as an example.
serial/__init__.py
import sys
if sys.platform == 'cli':
from serial.serialcli import Serial
else:
import os
# chose an implementation, depending on os
if os.name == 'nt': # sys.platform == 'win32':
from se...
Using 'return' in a Ruby block
...; }
LocalJumpError: unexpected return
from (irb):7:in `block in irb_binding'
from (irb):2:in `call'
from (irb):2:in `thing'
from (irb):6
from /home/mirko/.rvm/rubies/ruby-1.9.1-p378/bin/irb:15:in `<main>'
irb(main):009:0> thing { break 6 * 7 }
=> 4...
How to specify data attributes in razor, e.g., data-externalid=“23151” on @this.Html.CheckBoxFor(…)
...heckBox",
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 for all Html helpers taking a htmlAttributes anonymou...
How do I download a tarball from GitHub using cURL?
I am trying to download a tarball from GitHub using cURL , but it does not seem to be redirecting:
5 Answers
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How to concatenate strings in django templates?
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I was totally confused by this answer as it uses the include tag instead of the extend tag, but apparently it just works. Though I would recommend Ahsan's own answer as it also workes and is (in my opinion) semantically more correct a...