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Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...
Do try/catch blocks hurt performance when exceptions are not thrown?
... {
Console.WriteLine(ex.ToString());
}
finally
{
d = Math.Sin(d);
}
}
w.Stop();
Console.Write(" try/catch/finally: ");
Console.WriteLine(w.ElapsedMilliseconds);
w.Reset();
d = 0;
w.Start();
for (int i = ...
How do I add a placeholder on a CharField in Django?
...
Look at the widgets documentation. Basically it would look like:
q = forms.CharField(label='search',
widget=forms.TextInput(attrs={'placeholder': 'Search'}))
More writing, yes, but the separation allows for better abstraction of more complic...
In a .csproj file, what is for?
...
Helpful, but why have a "None" item at all, if the file is not to be included in the output? What's the point?
– JimH44
Apr 23 '18 at 9:03
1
...
How do I get the result of a command in a variable in windows?
...
If you have to capture all the command output you can use a batch like this:
@ECHO OFF
IF NOT "%1"=="" GOTO ADDV
SET VAR=
FOR /F %%I IN ('DIR *.TXT /B /O:D') DO CALL %0 %%I
SET VAR
GOTO END
:ADDV
SET VAR=%VAR%!%1
:END
All output lines are stor...
How to make a chain of function decorators?
...her object
scream = shout
# Notice we don't use parentheses: we are not calling the function,
# we are putting the function "shout" into the variable "scream".
# It means you can then call "shout" from "scream":
print(scream())
# outputs : 'Yes!'
# More than that, it means you can remove the old...
Store JSON object in data attribute in HTML jQuery
...in the text just use $('#myElement').data('key',jsonObject);
it won't actually be stored in the html, but if you're using jquery.data, all that is abstracted anyway.
To get the JSON back don't parse it, just call:
var getBackMyJSON = $('#myElement').data('key');
If you are getting [Object Objec...
What do commas and spaces in multiple classes mean in CSS?
..._12 .grid_6,
.container_16 .grid_8 {
width: 460px;
}
That says "make all .grid_6's within .container_12's and all .grid_8's within .container_16's 460 pixels wide." So both of the following will render the same:
<div class="container_12">
<div class="grid_6">460px Wide</div&g...
What's the difference between a word and byte?
I've done some research.
A byte is 8 bits and a word is the smallest unit that can be addressed on memory. The exact length of a word varies. What I don't understand is what's the point of having a byte? Why not say 8 bits?
...
How to disable Crashlytics during development
...orting from the Crashlytics web dashboard for the debug version.
Wrap the call to Crashlytics.start() in an if statement that checks a debug flag. You could use either a custom flag or an approach like the ones proposed here: How to check if APK is signed or "debug build"?
...