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Test for existence of nested JavaScript object key
...t step by step if you don't want a TypeError because if one of the members is null or undefined, and you try to access a member, an exception will be thrown.
You can either simply catch the exception, or make a function to test the existence of multiple levels, something like this:
function checkN...
Elegant way to check for missing packages and install them?
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Yes. If you have your list of packages, compare it to the output from installed.packages()[,"Package"] and install the missing packages. Something like this:
list.of.packages <- c("ggplot2", "Rcpp")
new.packages <- list.of.packages[!(list.o...
What is the equivalent of bigint in C#?
What am I supposed to use when handling a value in C#, which is bigint for an SQL Server database?
10 Answers
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How can I write output from a unit test?
...nsole.Write(Line) simply gets skipped over while debugging and the output is never printed. Calls to these functions from within classes I'm using work fine.
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Is there a method to generate a UUID with go language
I have code that looks like this:
12 Answers
12
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What is the difference between javac and the Eclipse compiler?
Is Eclipse's Java compiler just a wrapper around the same core that the javac program is wrapped around, or is it a separate compiler altogether? If the latter, why would they reinvent the wheel?
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How does HTTP file upload work?
When I submit a simple form like this with a file attached:
5 Answers
5
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Passing a std::array of unknown size to a function
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Is there a simple way to make this work, as one would with plain C-style arrays?
No. You really cannot do that unless you make your function a function template (or use another sort of container, like an std::vector, as sug...
How do you connect to multiple MySQL databases on a single webpage?
...e same you need to pass true for the '$new_link' (fourth) parameter, otherwise the same connection is reused. For example:
$dbh1 = mysql_connect($hostname, $username, $password);
$dbh2 = mysql_connect($hostname, $username, $password, true);
mysql_select_db('database1', $dbh1);
mysql_select_db('d...
Prevent BODY from scrolling when a modal is opened
...while the Modal (from http://twitter.github.com/bootstrap ) on my website is opened.
41 Answers
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