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How can I reset a react component including all transitively reachable state?
I occasionally have react components that are conceptually stateful which I want to reset. The ideal behavior would be equivalent to removing the old component and readding a new, pristine component.
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How to check if a file exists in Documents folder?
... Or just [0] via index accessing
– temporary_user_name
Dec 16 '14 at 0:09
firstObject is more safe than [0] a...
Is it safe to resolve a promise multiple times?
... rejected), that is it for a defered object - it is done.
If you should call then(...) on it's promise again, you should immediately get the (first) resolved/rejected result.
Additional calls to resolve() will not (should not?) have any effect. Not sure what happens if you attempt to reject a de...
How do I trap ctrl-c (SIGINT) in a C# console app
...
Actually, that article recommends P/Invoke, and CancelKeyPress is mentioned only briefly in the comments. A good article is codeneverwritten.com/2006/10/…
– bzlm
Aug 21 '10 at 7:55
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Naming of ID columns in database tables
...e wrong records.
If you would like to use the USING syntax that some dbs allow, you cannot if you use ID.
If you use ID you can easily end up with a mistaken join if you happen to be copying the join syntax (don't tell me that no one ever does this!)and forget to change the alias in the join con...
How to get the name of the calling method?
...eem to work in Rails 5.2.1. In Rails controller this returns "block in make_lambda". I guess this is for Ruby only.
– dcangulo
Nov 14 '18 at 4:59
add a comment
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Programmatically saving image to Django ImageField
...import File # you need this somewhere
import urllib
# The following actually resides in a method of my model
result = urllib.urlretrieve(image_url) # image_url is a URL to an image
# self.photo is the ImageField
self.photo.save(
os.path.basename(self.url),
File(open(result[0], 'rb'))
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Counter increment in Bash loop not working
...ot updating. Is it due to subshell thats getting created? How can I potentially fix this?
13 Answers
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How do I force Postgres to use a particular index?
...of why and what you can do instead can be found here. The reasons are basically that it's a performance hack that tends to cause more problems later down the line as your data changes, whereas PostgreSQL's optimizer can re-evaluate the plan based on the statistics. In other words, what might be a go...
Best way to initialize (empty) array in PHP
...ferent ways, with the literal grammar not being dogged by the overhead of calling a function.
PHP, on the other hand, has language constructs that may look like functions but aren't treated as such. Even with PHP 5.4, which supports [] as an alternative, there is no difference in overhead because...