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How to verify if a file exists in a batch file?
... IF /? help file: The ELSE clause must occur on the same line as the command after the IF. This burned me. hope it helps you.
– funkymushroom
Feb 27 '14 at 17:58
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How to convert An NSInteger to an int?
... To be precise, I think NSInteger is an int on 32-bit platforms, and a long on 64-bit platforms.
– Frédéric Adda
Mar 11 '14 at 22:16
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What is “:-!!” in C code?
... effect, a way to check whether the expression e can be evaluated to be 0, and if not, to fail the build.
The macro is somewhat misnamed; it should be something more like BUILD_BUG_OR_ZERO, rather than ...ON_ZERO. (There have been occasional discussions about whether this is a confusing name.)
You...
Extract value of attribute node via XPath
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What if I have a list of attributes and I need their values? string() seems to return just the first value.
– Konstantin Milyutin
Sep 18 '19 at 19:24
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Converting string from snake_case to CamelCase in Ruby
...ssify returns a string, whereas #constantize looks up constant in context (and does need camelize). 'active_record'.constantize gives error, 'active_record'.camelize.constantize returns the constant ActiveRecord, 'active_record'.classify returns the string 'ActiveRecord'. And if you did 'no_class'.c...
What is the difference between char array and char pointer in C?
I am trying to understand pointers in C but I am currently confused with the following:
8 Answers
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Number of elements in a javascript object
... implementations might keep track of such a value internally, there's no standard way to get it.
In the past, Mozilla's Javascript variant exposed the non-standard __count__, but it has been removed with version 1.8.5.
For cross-browser scripting you're stuck with explicitly iterating over the pro...
How do I install an R package from source?
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If you have the file locally, then use install.packages() and set the repos=NULL:
install.packages(path_to_file, repos = NULL, type="source")
Where path_to_file would represent the full path and file name:
On Windows it will look something like this: "C:\\RJSONIO_0.2-3.tar.gz...
How do I use the includes method in lodash to check if an object is in the collection?
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The includes (formerly called contains and include) method compares objects by reference (or more precisely, with ===). Because the two object literals of {"b": 2} in your example represent different instances, they are not equal. Notice:
({"b": 2} === {"b": 2})
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How to convert a string to utf-8 in Python
...icode'>)
^ This is the difference between a byte string (plain_string) and a unicode string.
>>> s = "Hello!"
>>> u = unicode(s, "utf-8")
^ Converting to unicode and specifying the encoding.
In Python 3
All strings are unicode. The unicode function does not exist anymore. See ...