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How to test if list element exists?
... to check that the name is actually defined in the list:
foo <- list(a=42, b=NULL)
foo
is.null(foo[["a"]]) # FALSE
is.null(foo[["b"]]) # TRUE, but the element "exists"...
is.null(foo[["c"]]) # TRUE
"a" %in% names(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[[...
Unicode equivalents for \w and \b in Java regular expressions?
... That way, a regex like \w+ matches words like hello , élève , GOÄ_432 or gefräßig .
3 Answers
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Intellij shortcut to convert code to upper or lower case?
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477
Ctrl + Shift + U
In the future try typing: Ctrl + Shift + A and look for any actions you like...
Pairs from single list
... section.
– Apalala
Jan 7 '11 at 18:40
@Apalala: zip does advance the same iterator twice.
– Joc...
How to give Jenkins more heap space when it´s started as a service under Windows?
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see also stackoverflow.com/questions/14762162/…
– user817795
Aug 28 '17 at 3:40
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Further understanding setRetainInstance(true)
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94
Ok, perhaps I was slightly too harsh on the Android documentation, because it does have some use...
What is the MySQL VARCHAR max size?
...he limit is lower if you use a multi-byte character set like utf8 or utf8mb4.
Use TEXT types inorder to overcome row size limit.
The four TEXT types are TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT. These correspond to the four BLOB types and have the same maximum lengths and storage requirements.
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How to get a ListBox ItemTemplate to stretch horizontally the full width of the ListBox?
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474
I'm sure this is a duplicate, but I can't find a question with the same answer.
Add Horizonta...
How to test chrome extensions?
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answered May 24 '10 at 18:44
KinlanKinlan
15.1k44 gold badges4747 silver badges8484 bronze badges
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Ant task to run an Ant target only if a file exists?
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edited Feb 15 '13 at 23:49
answered Feb 6 '09 at 14:53
to...