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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...happen in a particular order, and some have specific use cases.
Braces as Token Delimiters
The ${var} syntax is primarily used for delimiting ambiguous tokens. For example, consider the following:
$ var1=foo; var2=bar; var12=12
$ echo $var12
12
$ echo ${var1}2
foo2
Braces in Array Expansions
T...
#ifdef vs #if - which is better/safer as a method for enabling/disabling compilation of particular s
...rather than 0/1 in your #define, and because the value is a single lexical token, it's the one time you don't need parentheses around it.
#define DEBUG_ENABLED true
instead of
#define DEBUG_ENABLED (1)
share
...
How to make sure that string is valid JSON using JSON.NET
...method).
(Using JSON.Net)
Simplest way would be to Parse the string using JToken.Parse, and also to check if the string starts with { or [ and ends with } or ] respectively (added from this answer):
private static bool IsValidJson(string strInput)
{
if (string.IsNullOrWhiteSpace(strInput)) { ret...
Make Https call using HttpClient
....github.com");
client.DefaultRequestHeaders.Add(
"Authorization",
"token 123456789307d8c1d138ddb0848ede028ed30567");
client.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Add(
"User-Agent",
"Mozilla/5.0 (Wi...
How can a web application send push notifications to iOS devices? [closed]
...ive app is registered for push notification, it can send the authorization token to the server, which can be used in conjunction with the certificate used to provision the native client, to send the push notifications to the mobile device.
As specified in another answer, one option is to 'wrap' yo...
How to avoid reverse engineering of an APK file?
...ecure channel were compromised.
Once verified, the server transmits back a token over the channel. The token is only useful within the secure session, is composed of either random noise or an encrypted (and thus verifiable) copy of the session identifiers, and the client application must send this t...
How to print a string in fixed width?
...
the % character informs python it will have to substitute something to a token
the s character informs python the token will be a string
the 5 (or whatever number you wish) informs python to pad the string with spaces up to 5 characters.
In your specific case a possible implementation could look...
How do I get LaTeX to hyphenate a word that contains a dash?
...erref warning when I use it in a chapter string: Package hyperref Warning: Token not allowed in a PDF string. There, the other proposed solution (\def\hyph{-\penalty0\hskip0pt\relax}) works.
– Dr. Jan-Philip Gehrcke
Aug 26 '14 at 12:22
...
Determine installed PowerShell version
...
Use $PSVersionTable.PSVersion to determine the engine version. If the variable does not exist, it is safe to assume the engine is version 1.0.
Note that $Host.Version and (Get-Host).Version are not reliable - they reflect
the ver...
How to unstash only certain files?
...ath/To/MyFile.txt |sc Path/To/MyFile.txt - the backticks are necessary for PS to not interpret the braces specially, and the sc is necessary because PS's > operator defaults to UTF-16 (actually UCS-2) which is probably not what you want. @Balamurugan A's answer doesn't suffer from these issues.
...