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How can I check if a var is a string in JavaScript?
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Guys, I really would give an accepted answer to both of you, but I can't, all I can do is +1 to both, than give the accepted answer at who is more near to my specific problem, that I've not fully explained.
– vitt...
How to check for null in Twig?
... Notice: as Twig 2.x check for variable is equal to value like is_ sameas must be {% if var is same as(false) %} not {% if var is sameas(false) %} see Doc url => twig.symfony.com/doc/2.x/tests/sameas.html
– ahmed hamdy
Jul 15 '19 at 17:01
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How to delete migration files in Rails 3
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I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the...
XMLHttpRequest status 0 (responseText is empty)
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Why is this being downvoted? It is actually true! XHR requests from file:// URLs of files also on file:// URLs actually have status == 0 on success (tested on FF 24.0.5).
– Daniel Roethlisberger
Dec 31 '14 at 21:20
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Which is the correct C# infinite loop, for (;;) or while (true)? [closed]
...ve used and what I've seen others use for a loop that has to be broken manually.
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Make a Bash alias that takes a parameter?
...reate a function.
alias does not accept parameters but a function can be called just like an alias. For example:
myfunction() {
#do things with parameters like $1 such as
mv "$1" "$1.bak"
cp "$2" "$1"
}
myfunction old.conf new.conf #calls `myfunction`
By the way, Bash functions def...
find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Applying a function to every row of a table using dplyr?
...it reflects the fact that when you're doing row wise operations you're actually working with tuples from a list of vectors (the columns in a dataframe).
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Is the != check thread safe?
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Although strong evidence, bytecode is not actually a proof. It must be somewhere in the JLS as well...
– Marko Topolnik
Aug 27 '13 at 9:29
10
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Substitute multiple whitespace with single whitespace in Python [duplicate]
...ce characters that are combined.
To match unicode whitespace:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"\s+")
my_str = _RE_COMBINE_WHITESPACE.sub(" ", my_str).strip()
To match ASCII whitespace only:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"(?a:\s+)")
_RE_STRIP_WHITESPACE = re.co...