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MySQL CONCAT returns NULL if any field contain NULL
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answered Apr 1 '13 at 10:01
John WooJohn Woo
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How to check if object (variable) is defined in R?
...on of "...is defined". E.g.
> exists("foo")
[1] FALSE
> foo <- 1:10
> exists("foo")
[1] TRUE
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Is “for(;;)” faster than “while (TRUE)”? If not, why do people use it?
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answered Apr 9 '10 at 22:06
Ben ZottoBen Zotto
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How can I use break or continue within for loop in Twig template?
... break %}
<h2>{{ post.heading }}</h2>
{% if post.id == 10 %}
{% set break = true %}
{% endif %}
{% endfor %}
An uglier, but working example for continue:
{% set continue = false %}
{% for post in posts %}
{% if post.id == 10 %}
{% set continue = true %}...
How to check if a process id (PID) exists
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Getting Java version at runtime
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answered Apr 7 '10 at 9:08
polygenelubricantspolygenelubricants
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Check if a Bash array contains a value
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patrikpatrik
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How do I create a list of random numbers without duplicates?
I tried using random.randint(0, 100) , but some numbers were the same. Is there a method/module to create a list unique random numbers?
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How to include (source) R script in other scripts
....2.
– Michael Schubert
Dec 5 '13 at 10:52
The correct usage is `exists("foo") and the answer was edited.
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Why doesn't c++ have &&= or ||= for booleans?
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answered Mar 21 '10 at 20:02
Konrad RudolphKonrad Rudolph
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