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Techniques for Tracing Constraints
... and GHC complains could not deduce x ~ y for some x and y . You can usually throw GHC a bone and simply add the isomorphism to the function constraints, but this is a bad idea for several reasons:
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django: BooleanField, how to set the default value to true?
...fields/#django.forms.Field.initial ) like
class MyForm(forms.Form):
my_field = forms.BooleanField(initial=True)
If you're using a ModelForm, you can set a default value on the model field ( https://docs.djangoproject.com/en/2.2/ref/models/fields/#default ), which will apply to the resulting M...
Effects of changing Django's SECRET_KEY
...t know about 1.4, it's a matter of taking a look at the code. I pointed at all the sources for each point, you can take a look at "protect session data and create random session keys". It's normal you're still logged in but you won't be able to read the data contained in the session as SECRET_KEY is...
The order of elements in Dictionary
...when enumerating them:
foreach (KeyValuePair<string, string> kvp in _Dictionary.OrderBy(k => k.Value)) {
...
}
In framework 2.0 you would first have to put the items in a list in order to sort them:
List<KeyValuePair<string, string>> items = new List<KeyValuePair<str...
Where can I find Android source code online? [closed]
...plication(e.g.the contact application) ? Is the only way to go to download all there is?
7 Answers
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Why does C# forbid generic attribute types?
...pful information either, although it does provide an example of what's not allowed.
My copy of the annotated C# 3 spec should arrive tomorrow... I'll see if that gives any more information. Anyway, it's definitely a language decision rather than a runtime one.
EDIT: Answer from Eric Lippert (parap...
How do I efficiently iterate over each entry in a Java Map?
...erret The only reason you might want to use an iterator is if you need to call its remove method. If that is the case, this other answer shows you how to do it. Otherwise, the enhanced loop as shown in the answer above is the way to go.
– assylias
Oct 8 '12 at ...
Is it possible to use JavaScript to change the meta-tags of the page?
...
@bobince: Actually, the SKYPE_TOOLBAR one still takes effect if you insert it with js (which is useful as html5 validator doesn't like that meta tag).
– DaedalusFall
Nov 15 '11 at 13:23
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How can I avoid running ActiveRecord callbacks?
I have some models that have after_save callbacks. Usually that's fine, but in some situations, like when creating development data, I want to save the models without having the callbacks run. Is there a simple way to do that? Something akin to...
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The term “Context” in programming? [closed]
...roviding your PIN number at the ATM). Either way, it's information that usually helps to get stuff done.
Now let's say you take your $100 and buy a plane ticket to fly somewhere warm while your mouth heals.
You arrive at a nice sunny destination, but your bag doesn't make it. It's lost somewhere i...