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“unary operator expected” error in Bash if condition
...it's much easier to always use the double bracket conditional compound command [[ ... ]], instead of the Posix-compatible single bracket version [ ... ]. Inside a [[ ... ]] compound, word-splitting and pathname expansion are not applied to words, so you can rely on
if [[ $aug1 == "and" ]];
to co...
Customizing the template within a Directive
...in order for the form's controller to recognize its newly formed existence and include it in validation. I could not get it to work in a directive's compile property.
– m.e.conroy
Mar 24 '14 at 15:08
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IPC performance: Named Pipe vs Socket
...y? I would prefer to use sockets because they can do two-way communication and are very flexible but will choose speed over flexibility if it is by considerable amount.
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Painless way to install a new version of R?
Andrew Gelman recently lamented the lack of an easy upgrade process for R (probably more relevant on Windows than Linux). Does anyone have a good trick for doing the upgrade, from installing the software to copying all the settings/packages over?
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How to construct a WebSocket URI relative to the page URI?
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If your Web server has support for WebSockets (or a WebSocket handler module) then you can use the same host and port and just change the scheme like you are showing. There are many options for running a Web server and Websocket server/module together.
I would suggest that you look at t...
JSON Naming Convention (snake_case, camelCase or PascalCase) [closed]
Is there a standard on JSON naming? I see most examples using all lower case separated by underscore, aka snake_case , but can it be used PascalCase or camelCase as well?
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Most efficient way to concatenate strings in JavaScript?
In JavaScript, I have a loop that has many iterations, and in each iteration, I am creating a huge string with many += operators. Is there a more efficient way to create a string? I was thinking about creating a dynamic array where I keep adding strings to it and then do a join. Can anyone explain...
What are the uses of the exec command in shell scripts? [closed]
Can anyone explain what are the uses of the exec command in shell scripting with simple examples?
2 Answers
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Is there a standard function to check for null, undefined, or blank variables in JavaScript?
...re a universal JavaScript function that checks that a variable has a value and ensures that it's not undefined or null ? I've got this code, but I'm not sure if it covers all cases:
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How to serialize an object into a string
I am able to serialize an object into a file and then restore it again as is shown in the next code snippet. I would like to serialize the object into a string and store into a database instead. Can anyone help me?
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