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How do I limit the number of results returned from grep?
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The -m option is probably what you're looking for:
grep -m 10 PATTERN [FILE]
From man grep:
-m NUM, --max-count=NUM
Stop reading a file after NUM matching lines. If the input is
standard input from a regular file, and NUM matching lines are
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What is the difference between typeof and instanceof and when should one be used vs. the other?
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Use instanceof for custom types:
var ClassFirst = function () {};
var ClassSecond = function () {};
var instance = new ClassFirst();
typeof instance; // object
typeof instance == 'ClassFirst'; // false
instance instanceof Object; // true
in...
How can I convert a dictionary into a list of tuples?
...gt;>> d.items()
[('a', 1), ('c', 3), ('b', 2)]
>>> [(v, k) for k, v in d.iteritems()]
[(1, 'a'), (3, 'c'), (2, 'b')]
It's not in the order you want, but dicts don't have any specific order anyway.1 Sort it or organize it as necessary.
See: items(), iteritems()
In Python 3.x, you...
Swift Programming: getter/setter in stored property
How do I overwrite the setter of stored property in Swift?
5 Answers
5
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How to properly use unit-testing's assertRaises() with NoneType objects? [duplicate]
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If you are using python2.7 or above you can use the ability of assertRaises to be use as a context manager and do:
with self.assertRaises(TypeError):
self.testListNone[:1]
If you are using python2.6 another way beside the one given until now is ...
Java: possible to line break in a properties file?
...s you break across multiple lines, and whitespace that starts a line is ignored:
myStr = Hello \
World
The Java docs put it this way:
A logical line holds all the data of a key-element pair, which may be spread out across several adjacent natural lines by escaping the line terminator ...
Java 8 forEach with index [duplicate]
Is there a way to build a forEach method in Java 8 that iterates with an index? Ideally I'd like something like this:
3 A...
How can I join elements of an array in Bash?
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A 100% pure Bash function that supports multi-character delimiters is:
function join_by { local d=$1; shift; local f=$1; shift; printf %s "$f" "${@/#/$d}"; }
For example,
join_by , a b c #a,b,c
join_by ' , ' a b c #a , b , c
join_by ')|(' a b c #a)|(b)|(c
joi...
Pandas aggregate count distinct
Let's say I have a log of user activity and I want to generate a report of total duration and the number of unique users per day.
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Make virtualenv inherit specific packages from your global site-packages
I'm looking for a way to make a virtualenv which will contain just some libraries (which i chose) of the base python installation.
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