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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[["...
How to handle invalid SSL certificates with Apache HttpClient? [duplicate]
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edited May 1 '12 at 23:43
Gray
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Jquery live() vs delegate() [duplicate]
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edited Aug 6 '12 at 15:14
answered Jan 2 '11 at 15:55
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Python extract pattern matches
Python 2.7.1
I am trying to use python regular expression to extract words inside of a pattern
9 Answers
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Ant: How to execute a command for each file in directory?
...7
Sean
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answered Sep 23 '09 at 19:17
blak3rblak3r
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What Are the Differences Between PSR-0 and PSR-4?
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289
They are very similar so it is not surprising that it's a bit confusing. The summary is that P...
Providing a default value for an Optional in Swift?
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292
Update
Apple has now added a coalescing operator:
var unwrappedValue = optionalValue ?? defa...
JSON formatter in C#?
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answered Aug 24 at 11:36
Gurdeep Singh SidhuGurdeep Singh Sidhu
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Making HTTP Requests using Chrome Developer tools
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12 Answers
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