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Delete a dictionary item if the key exists [duplicate]

Is there any other way to delete an item in a dictionary only if the given key exists, other than: 3 Answers ...
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Bash ignoring error for a particular command

...e Manual explains, "The shell does not exit" when the -e attribute is set "if the command that fails is part of the command list immediately following a while or until keyword, part of the test in an if statement, part of any command executed in a && or || list except the command following t...
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Make first letter of a string upper case (with maximum performance)

...lly old answers public static string FirstCharToUpper(string input) { if (String.IsNullOrEmpty(input)) throw new ArgumentException("ARGH!"); return input.First().ToString().ToUpper() + String.Join("", input.Skip(1)); } EDIT: This version is shorter. For a faster solution take a lo...
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WAMP 403 Forbidden message on Windows 7

...The rule to allow 'from 127.0.0.1' should be enough to allow local access, if that is the main objective here, the 127.0.0.1 is basically a loop back to the network adaptor. If you type in the address bar 'http'://127.0.0.1:{portNumber}/{folderOrFileName}' it should work fine. This should work the s...
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Detecting an “invalid date” Date instance in JavaScript

I'd like to tell the difference between valid and invalid date objects in JS, but couldn't figure out how: 46 Answers ...
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How to mkdir only if a directory does not already exist?

...dir -p foo/bar/baz will create directories foo, foo/bar, and foo/bar/baz if they don't exist. Some implementation like GNU mkdir include mkdir --parents as a more readable alias, but this is not specified in POSIX/Single Unix Specification and not available on many common platforms like macOS, va...
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Javascript - removing undefined fields from an object [duplicate]

...key] === undefined && delete obj[key]) jsbin Same example using if expression: Object.keys(obj).forEach(key => { if (obj[key] === undefined) { delete obj[key]; } }); If you want to remove the items from nested objects as well, you can use a recursive function: const removeE...
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Read a file line by line assigning the value to a variable

... The following reads a file passed as an argument line by line: while IFS= read -r line; do echo "Text read from file: $line" done < my_filename.txt This is the standard form for reading lines from a file in a loop. Explanation: IFS= (or IFS='') prevents leading/trailing whitespace f...
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Using String Format to show decimal up to 2 places or simple integer

....99 or 100.9, What I want is to display the price in 2 decimal places only if the decimals are entered for that price , for instance if its 100 so it should only show 100 not 100.00 and if the price is 100.2 it should display 100.20 similarly for 100.22 should be same . I googled and came across som...
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Check if application is on its first run [duplicate]

...verride protected void onResume() { super.onResume(); if (prefs.getBoolean("firstrun", true)) { // Do first run stuff here then set 'firstrun' as false // using the following line to edit/commit prefs prefs.edit().putBoolean("firstrun", false)...