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Count number of objects in list [closed]
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zx8754
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answered Nov 16 '09 at 7:08
JoeyJoey
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Checking if a key exists in a JavaScript object?
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4314
Checking for undefined-ness is not an accurate way of testing whether a key exists. What if th...
find() with nil when there are no records
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173
Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Apply formula to the entire column
...OP wanted.
– Thanasis Kapelonis
May 3 '16 at 18:03
3
Thanks for sharing. It works fine for me but...
Completely uninstall PostgreSQL 9.0.4 from Mac OSX Lion?
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edited May 23 '17 at 12:18
Community♦
111 silver badge
answered Nov 7 '11 at 15:04
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How can I format my grep output to show line numbers at the end of the line, and also the hit count?
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dogbanedogbane
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Something like 'contains any' for Java set?
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543
Wouldn't Collections.disjoint(A, B) work? From the documentation:
Returns true if the two sp...
Use PHP to create, edit and delete crontab jobs?
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133
crontab command usage
usage: crontab [-u user] file
crontab [-u user] [ -e | -l | -r...
How to use R's ellipsis feature when writing your own function?
...luated expression".
When you call my_ellipsis_function(a=1:10,b=11:20,c=21:30) then ... "creates" a list of arguments: list(a=1:10,b=11:20,c=21:30) and substitute make it a list of four elements:
List of 4
$ : symbol list
$ a: language 1:10
$ b: language 11:20
$ c: language 21:30
First element d...
Could not insert new outlet connection [duplicate]
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answered Apr 24 '13 at 3:05
H LaiH Lai
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