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What is the difference between children and childNodes in JavaScript?
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347
Understand that .children is a property of an Element. 1 Only Elements have .children, and the...
how to concatenate two dictionaries to create a new one in Python? [duplicate]
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Slowest and doesn't work in Python3: concatenate the items and call dict on the resulting list:
$ python -mtimeit -s'd1={1:2,3:4}; d2={5:6,7:9}; d3={10:8,13:22}' \
'd4 = dict(d1.items() + d2.items() + d3.items())'
100000 loops, best of 3: 4.93 usec per loop...
Simultaneously merge multiple data.frames in a list
...question was marked as a duplicate of this one so I answer here, using the 3 sample data frames below:
x <- data.frame(i = c("a","b","c"), j = 1:3, stringsAsFactors=FALSE)
y <- data.frame(i = c("b","c","d"), k = 4:6, stringsAsFactors=FALSE)
z <- data.frame(i = c("c","d","a"), l = 7:9, stri...
Finding the PHP File (at run time) where a Class was Defined
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3 Answers
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How does PHP 'foreach' actually work?
...ction iterate($arr) {
foreach ($arr as $v) {}
}
$outerArr = [0, 1, 2, 3, 4];
iterate($outerArr);
Here, $arr will be duplicated to prevent IAP changes on $arr from leaking to $outerArr. In terms of the conditions above, the array is not a reference (is_ref=0) and is used in two places (refcoun...
_=> what does this underscore mean in Lambda expressions?
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3
It's more common in Haskell and other functional languages. I think that's where it comes from.
– Gabe Moothart
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In Ruby on Rails, what's the difference between DateTime, Timestamp, Time and Date?
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3 Answers
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What is a 'semantic predicate' in ANTLR?
... of semantic predicates in Antlr4
Semantic predicates in ANTLR4?
ANTLR 3
A semantic predicate is a way to enforce extra (semantic) rules upon grammar
actions using plain code.
There are 3 types of semantic predicates:
validating semantic predicates;
gated semantic predicates;
disambiguating...